How to Quote Modified Vehicles with Confidence

From horsepower upgrades to custom builds, modified vehicles don’t have to mean complicated placement.

Modified vehicles are some of the most personalized—and valuable—vehicles your clients own. From engine swaps and suspension upgrades to full custom builds, these vehicles represent time, money, and passion.

For many agents, vehicle modifications can create uncertainty at quote time.

• What gets rated as a modified vehicle?
• Do performance upgrades affect eligibility?
• What documentation is needed?

The good news: Modified vehicles can often be a strong fit for coverage through Hagerty. The key is knowing what to look for before you start the quote.

Hagerty considers a wide range of modified vehicles—including hot rods, resto mods, custom imports, replicas, and certain high-horsepower builds—when they meet program guidelines.

Here are our top tips for quoting modified vehicles with Hagerty:

1. Understand what “modified” really means

Not every modification changes eligibility. Get our Stock vs. Modified one-pager here.

Generally, modifications that significantly alter performance, appearance, or vehicle structure can affect how a vehicle is classified and quoted.

Examples include:

• Engine performance upgrades
• Suspension modifications
• Custom paint or bodywork
• Wheel and tire changes
• Drivetrain swaps
• Replica builds

Knowing the degree of modification helps set expectations upfront.

2. Ask about horsepower early

Horsepower matters—especially on performance-focused builds.

Vehicles with 650+ horsepower may still qualify with Hagerty, but additional underwriting criteria may apply, including driving history, prior experience with high-performance vehicles, and minimum vehicle value thresholds.

Early conversations about powertrain modifications can save time and avoid surprises later.

Use this Modified Vehicle Worksheet to capture details.

3. Documentation helps move faster

Modified vehicles are often one-of-one. That means documentation matters.

Encourage clients to have:

• Updated photos
• Build receipts
• Appraisals (when applicable)
• Modification lists

Clear documentation helps establish vehicle value and can streamline underwriting.

4. Lead with value—not depreciation

One of the biggest risks with modified vehicles is underinsuring the investment.

A standard policy may not account for customization, specialty parts, or labor invested into the build.

With Guaranteed Value®, clients know the agreed value upfront and have peace of mind that their investment is properly protected in the event of a covered loss. Protecting your clients’ modified vehicles through Hagerty can become a major differentiator and referral source for your agency.

Cover your bases when quoting with the Agent Fact Finder Worksheet.

Modified doesn’t have to mean complicated.

Modified vehicles are everywhere—from classic hot rods to modern custom imports.

When you understand the vehicle, the build, and the client’s goals, selecting coverage becomes much simpler.

Explore Hagerty’s modified vehicle eligibility guidelines and quote with greater confidence.