How to Prove Custom Vehicle Modifications in a Tempe Insurance Claim

If you’ve put time and money into customizing your vehicle—whether it's upgraded suspension, aftermarket wheels, a premium sound system, or a full engine rebuild—you expect that investment to be protected. But after a crash in Tempe, getting an insurance company to recognize the value of those modifications can feel like an uphill battle.

Insurers are notorious for undervaluing modified vehicles or ignoring custom parts altogether. Without the right documentation, you could be left with a settlement that only reflects the “stock” version of your car—leaving thousands of dollars unrecovered. At Tempe Car Accident Attorney, we help car owners fight back and prove every dollar of value tied to custom work.

Why Custom Modifications Often Get Overlooked

Insurance companies are primarily focused on actual cash value (ACV)—what your car was worth at the time of the crash based on year, mileage, and condition. Unless you’ve previously declared your upgrades, they’ll likely assume your vehicle is in standard factory condition.

We’ve seen this happen across North Tempe, Downtown Tempe, and Escalante, where even well-documented vehicles had aftermarket upgrades ignored by adjusters—until legal pressure brought the full value into play.

Step 1: Gather Proof of All Modifications

The strongest tool in any custom vehicle insurance claim is documentation. You’ll want to provide:

• Receipts for parts and labor

• Before-and-after photos

• Installation invoices from shops or mechanics

• Manufacturer descriptions of the aftermarket parts used

• Valuation reports from third-party appraisers if available

This applies to both performance and cosmetic upgrades. Whether it’s a suspension kit, ECU tune, carbon fiber body panels, or a custom wrap, you’ll need to show what was added, when it was added, and how much it cost.

If your car was damaged in a T-bone accident or rollover crash, and the aftermarket parts were destroyed, having high-resolution photos becomes especially important.

Step 2: Show the Value Before the Crash

Don’t rely on the insurance company’s valuation software—they usually base estimates on Kelley Blue Book or NADA data, which don’t reflect custom work. You’ll want to establish the vehicle’s fair market value with modifications.

We’ve helped clients in Holdeman and Meyer Park use specialty valuation tools like Edmunds “True Market Value” or bring in appraisals from custom car shops to challenge lowball offers. The more documentation you can show that the modifications increased the car’s value, the stronger your claim.

Step 3: Understand Your Insurance Coverage

Many drivers assume customizations are automatically covered—but unless you’ve added custom parts and equipment (CPE) coverage to your policy, your insurer may limit or exclude aftermarket parts altogether. Standard auto policies often cap custom equipment coverage at $1,000–$2,500.

If you’re involved in a DUI crash, hit-and-run incident, or rideshare accident, understanding your coverage is key—because some types of damage (especially cosmetic or lighting upgrades) are disputed more aggressively depending on fault and policy limits.

Step 4: Make a Specific Demand

When submitting your property damage claim, don’t just expect the adjuster to find or evaluate your upgrades. Spell it out. Include a detailed itemized list of every aftermarket addition, the cost of each, and how they contributed to your car’s value at the time of the crash.

For example, if your vehicle had:

• Aftermarket wheels and tires ($2,000)

• Lift kit and suspension upgrades ($3,500)

• Custom stereo system with amp/subwoofer ($1,200)

• Ceramic tint and wrap ($1,000)

Then your demand should include $7,700 above base market value—with supporting receipts and photos.

Drivers in South Tempe and Tempe’s student-heavy neighborhoods often run into resistance on claims like these, especially when insurance adjusters say things like “that’s considered cosmetic” or “we only cover stock value.” That’s not the final word—Arizona law allows you to contest those denials.

Step 5: Be Ready to Negotiate—or Litigate

Insurance companies will likely counter with a reduced offer—or ignore certain upgrades entirely. At that point, having legal counsel makes all the difference. We’ve had clients recover thousands in previously denied upgrades after filing a formal demand backed by expert appraisals and Arizona property damage statutes.

This is especially crucial in crashes involving uninsured drivers, where your own insurer may drag out reimbursement or dispute your valuation.

If your car is declared a total loss, insurers will usually subtract custom upgrades from the base payout unless you proactively include them in your claim. We go deeper into that process here.

What If the Parts Were Not Professionally Installed?

Insurers may try to deny compensation for DIY modifications, claiming they weren’t professionally installed. However, self-installed parts can still be reimbursed—as long as you have receipts and clear photos showing that the work was complete and functional prior to the crash.

We’ve helped drivers with garage-built drift cars, performance-tuned daily drivers, and off-road vehicles recover value for their upgrades—even when the work was done outside of a shop. The key is showing it added to the vehicle’s fair market value and was not related to the cause of the accident.

What If You Need to Replace the Parts Instead?

In some situations, it makes more sense to repair or replace specific modifications rather than include them in a total loss valuation. This is common in partial-loss claims, like rear-end collisions or fender damage, where the car isn’t totaled but aftermarket parts are damaged.

In those cases, we help clients include replacement costs for things like body kits, tail lights, exhaust systems, and underglow—ensuring insurers cover the parts they otherwise try to ignore.

Final Thoughts: Modified Cars Deserve Full Compensation Too

Your modifications weren’t free—and if someone else caused your crash, they shouldn’t be ignored just because your car wasn’t “stock.” With documentation, persistence, and legal strategy, you can recover the full value of your custom upgrades—even if the insurance company tries to say otherwise.

If your customized vehicle was damaged in a crash anywhere in Tempe—from North Tempe to Escalante—don’t let the insurer lowball your claim. Visit our legal resources or contact us directly to get help proving your vehicle’s true worth.