Cost Segregation Study
A full engineering-based analysis that reclassifies property assets into 5-, 7-, or 15-year depreciation schedules — unlocking front-loaded deductions and delivering an average first-year savings of $171,243.
Illinois property owners are leaving serious tax money on the table. Seneca Cost Segregation's engineering-based studies reclassify your assets into shorter depreciation schedules, turning 20–40% of your property's cost into immediate deductions. With over 10,200 studies completed nationwide and an average first-year savings of $171,243, discover how much you could keep from your next Illinois tax bill.
Comprehensive engineering-based studies and supporting services to maximize your Illinois real estate tax savings.
A full engineering-based analysis that reclassifies property assets into 5-, 7-, or 15-year depreciation schedules — unlocking front-loaded deductions and delivering an average first-year savings of $171,243.
Missed depreciation on a property placed in service up to 15 years ago? Our lookback studies use IRS Form 3115 to recapture all missed deductions in a single tax year — no amended returns required.
Skip costly on-site visits. Our engineering team conducts full property inspections via video call in 30–45 minutes, delivering faster turnaround times of 2–3 weeks at reduced overall study cost.
We work directly with your accountant to seamlessly implement depreciation schedules into current or prior-year tax returns, ensuring your CPA has everything needed to file accurately and confidently.
Every study includes our Seneca AuditDefense guarantee — we defend your report against IRS inquiries at no extra charge for the life of your property ownership, backed by a money-back guarantee.
Facing a tax deadline? Our expedited service delivers completed cost segregation studies in as little as one week, so Illinois investors never miss a critical filing window.
We assess your Illinois property's eligibility, provide a transparent preliminary savings estimate and ROI projection, and explain exactly how cost segregation applies to your specific property type — whether it's a Chicago apartment complex, a downstate retail center, or a single-family rental.
See how Illinois and nationwide property owners are unlocking six-figure tax savings with Seneca Cost Segregation.
"The tax savings achieved with Seneca Cost Segregation made a major impact on my bottom line. I wasn't aware it was a possibility until they brought the opportunity to me. Their insight and expertise are invaluable."
"We contacted Seneca for a Cost Seg Study and they went above and beyond. Their eagerness to help and province of info will blow you away."
"Dylan and his team at Seneca Cost Segregation are extremely knowledgeable. When I explored their website, it was clear they knew their stuff. It offered a very professional approach to cost segregation, backed by years of experience."
"I couldn't be more pleased with the results. Their team was incredibly professional, prompt, and easy to work with. I achieved a highly favorable tax situation and recommend Seneca to anyone looking to maximize their tax benefits."
"We contacted Dylan for a cost seg study and he went above and beyond Not only will their pricing be the best price you will find, his eagerness to help and province info will blow you away"
"I've referred multiple clients to Seneca, and each time they uncovered significant tax savings. Their team is fast, professional, and easy to work with. They've become a trusted extension of our tax strategy."
"Extremely professional and efficient in their cost set analysis. Great communication and transparency. Will be using them going forward on all my properties."
"Their team was incredibly professional, prompt, and easy to work with."
"Seamless experience with great results. Highly recommend!"
"The tax savings achieved with Seneca Cost Segregation made a major impact on my bottom line. I wasn't aware it was a possibility until they brought the opportunity to me. Their insight and expertise are invaluable."
"We contacted Seneca for a Cost Seg Study and they went above and beyond. Their eagerness to help and province of info will blow you away."
"Dylan and his team at Seneca Cost Segregation are extremely knowledgeable. When I explored their website, it was clear they knew their stuff. It offered a very professional approach to cost segregation, backed by years of experience."
"I couldn't be more pleased with the results. Their team was incredibly professional, prompt, and easy to work with. I achieved a highly favorable tax situation and recommend Seneca to anyone looking to maximize their tax benefits."
"We contacted Dylan for a cost seg study and he went above and beyond Not only will their pricing be the best price you will find, his eagerness to help and province info will blow you away"
"I've referred multiple clients to Seneca, and each time they uncovered significant tax savings. Their team is fast, professional, and easy to work with. They've become a trusted extension of our tax strategy."
"Extremely professional and efficient in their cost set analysis. Great communication and transparency. Will be using them going forward on all my properties."
"Their team was incredibly professional, prompt, and easy to work with."
"Seamless experience with great results. Highly recommend!"
"The tax savings achieved with Seneca Cost Segregation made a major impact on my bottom line. I wasn't aware it was a possibility until they brought the opportunity to me. Their insight and expertise are invaluable."
"We contacted Seneca for a Cost Seg Study and they went above and beyond. Their eagerness to help and province of info will blow you away."
"Dylan and his team at Seneca Cost Segregation are extremely knowledgeable. When I explored their website, it was clear they knew their stuff. It offered a very professional approach to cost segregation, backed by years of experience."
"I couldn't be more pleased with the results. Their team was incredibly professional, prompt, and easy to work with. I achieved a highly favorable tax situation and recommend Seneca to anyone looking to maximize their tax benefits."
"We contacted Dylan for a cost seg study and he went above and beyond Not only will their pricing be the best price you will find, his eagerness to help and province info will blow you away"
"I've referred multiple clients to Seneca, and each time they uncovered significant tax savings. Their team is fast, professional, and easy to work with. They've become a trusted extension of our tax strategy."
"Extremely professional and efficient in their cost set analysis. Great communication and transparency. Will be using them going forward on all my properties."
"Their team was incredibly professional, prompt, and easy to work with."
"Seamless experience with great results. Highly recommend!"
Illinois real estate investors trust Seneca for accurate, compliant, and fast cost segregation studies that consistently deliver outsized returns.
Over 10,200 studies completed nationwide with a 95% client referral rate — Illinois investors rely on results, not promises.
Our proprietary, engineer-built technology ensures IRS-compliant precision, reducing audit risk for Illinois property owners under scrutiny.
Founded by real estate investors who have operated across markets — our team understands Illinois property dynamics and tax implications firsthand.
Every study includes lifetime IRS audit defense at no extra cost — protecting your Illinois investment for as long as you own the property.
Experienced founders and specialists dedicated to maximizing your real estate tax savings.
Co-Founder and CEO
Dylan Scandalios is a seasoned real estate investor with a multi-family property portfolio in the Pacific Northwest and a deep command of cost segregation strategy. Before founding Seneca Cost Segregation, Dylan closed millions of dollars in business for both public and private companies along the West Coast, building the client-focused, results-driven culture that defines Seneca today. As CEO, Dylan has guided the firm to complete over 10,200 cost segregation studies nationwide — including hundreds for Illinois investors navigating complex commercial and residential real estate portfolios. His hands-on investment background means he speaks the language of his clients: return on investment, cash flow optimization, and tax-efficient wealth building. Under Dylan's leadership, Seneca maintains a 95% client referral rate and an average first-year client savings of $171,243.
Co-Founder
Paul Spies brings a rare combination of military discipline, real estate construction expertise, and hands-on investment experience to Seneca Cost Segregation. A Marine Corps Sergeant, Paul spent over 8 years in real estate construction before successfully flipping more than 150 homes in just four years and leading ground-up multi-family development projects. As a Principal Broker and Licensed Contractor, he has seen firsthand how cost segregation transforms the economics of real estate investment — having personally leveraged the strategy since 2018. Paul co-founded Seneca to make engineering-grade cost segregation studies accessible and affordable for every real estate investor, from Illinois apartment owners in Chicago to commercial property holders downstate, delivering studies on time and without compromise.
Chairman
Howard Hirsch serves as Chairman of Seneca Cost Segregation, providing strategic oversight and governance that supports the company's mission to deliver best-in-class cost segregation studies to real estate investors across the country. His leadership helps ensure Seneca maintains the highest standards of engineering integrity, IRS compliance, and client service — values that Illinois property owners and their CPAs depend on when making significant tax strategy decisions.
President/Treasurer
Harry Papp serves as President and Treasurer of Seneca Cost Segregation, overseeing operations and financial management to ensure the firm delivers consistent, high-quality studies at competitive and transparent pricing. His role is central to maintaining Seneca's commitment to affordability and financial accountability — core principles that make cost segregation accessible to Illinois real estate investors at every scale, from single-family rental owners to large commercial property portfolios.
For the 2026 tax year, Illinois offers a personal exemption allowance of $2,425 per taxpayer (subject to annual legislative adjustment). However, cost segregation studies primarily accelerate federal depreciation deductions under IRS guidelines, which flow through to Illinois state returns. This means the federal savings generated by cost segregation often dwarf state exemption thresholds — making it a far more powerful tool for Illinois property owners.
Speak with a Seneca specialist for a free, no-obligation consultation tailored to your Illinois property.
Seneca Cost Segregation serves real estate investors and property owners across every Illinois market, from Chicago to the collar counties and beyond.
All 50 States
Service Coverage
10,200+
Studies Completed
95%
Client Referral Rate
We serve property owners across all of Illinois — contact us to confirm coverage and get your free estimate.
Certified member of the American Society of Cost Segregation Professionals.
Perfect five-star rating from satisfied clients nationwide.
Proudly founded and operated by a U.S. Marine Corps veteran.
Tell us about your Illinois property and we'll provide a no-obligation preliminary analysis showing your estimated first-year tax savings, ROI projection, and study cost — typically within 24 hours.
For immediate assistance, feel free to give us a direct call at +1 530-797-6539 You can also send us a quick email at info@senecacostseg.com
For immediate assistance, feel free to give us a direct call at +1 530-797-6539 You can also send us a quick email at info@senecacostseg.com