Years ago, a Denver homeowner who was unhappy with the assessed value of his property mailed a square of purple shag carpet as evidence his home’s value needed to be lower.

The carpet sample came sealed in a plastic Ziplock bag as part of the homeowner’s appeal package, Denver Assessor Keith Erffmeyer said.

“I keep thinking back to that and think, ‘Why didn’t you send a picture instead of cutting up a sample?’” he said. “We’ve seen all kinds of things.”

But did it work?

Erffmeyer, who has worked in the Denver Assessor’s Office for 29 years, said he doesn’t remember exactly.

“My guess is if they went to that length, it was an ‘A’ for effort and we gave them something,” he said.

But Erffmeyer doesn’t recommend people who appeal their property valuations this year take the same strategy. A picture will do.

Colorado’s county property assessors calculated unprecedented gains in home values and mailed notices to homeowners earlier this month. Median increases in residential properties, calculated every two years, shot up between 30% to nearly 50% across metro Denver. Those higher home values are expected to result in significant property tax increases next year, although it’s too early to know exactly how much those tax assessments will go up.

Now, assessors along the Front Range are reporting record numbers of appeals and are preparing to receive thousands more before the June 8 deadline.

But what’s the best strategy to challenge a home valuation that you believe is too high?

To find out, The Denver Post interviewed Adams County Assessor Ken Musso, Arapahoe County Assessor P.K. Kaiser, Denver County Assessor Keith Erffmeyer, Douglas County Assessor Toby Damisch and Jefferson County Assessor Scot Kersgaard, and got advice on how to file a successful appeal.

Here are some important things to know about the process:

Your property value was based on a mass-modeling algorithm that used data from comparable homes sold in your neighborhood.

Those mass models do not look at individual properties. But when you appeal your home’s valuation, an appraiser then will review your particular parcel and then check comparable sales based on your specific house and neighborhood.

Appeals are free.

Property assessors do not charge a fee to appeal. Assessors say fewer than half of the people who appeal are successful. In Jefferson County, for example, about 15% of those who appealed found the assessor agreeing with their numbers, while another third managed to bring down their valuation to some degree.

Meet the deadline.

State law sets a June 8 deadline for filing an appeal. If you miss the deadline, the law gives you a two-year window — until January 2026 — to file an abatement petition. If you win, you will receive a refund of property taxes already paid.

File online, by mail or in person.

Your county’s notice of valuation card or letter includes information on filing an appeal. Each county’s website lists steps for filing a protest.

Adams County: adcogov.org/appeals-process
Arapahoe County: tinyurl.com/36yjdbjc
Boulder County: tinyurl.com/2p8tbsz5
Broomfield: tinyurl.com/2p9bch9m
Denver: tinyurl.com/4ryjsr6f
Douglas County: douglas.co.us/assessor/appeals
Jefferson County: jeffco.us/431/Appeals

Understand what you are appealing.

Your new property valuation is actually based on your home’s value as of June 30, 2022. Although most Colorado home values have dropped during the past 11 months, that argument won’t help your appeal. You have to base your case on the condition of your home and comparable sales at that time.

Double-check your property records.

Each assessor’s office has a detailed record of your property. You can check those records for free online to make sure the assessor’s information is accurate. Sometimes, there are mistakes such as a miscalculation of the square footage or wrong information about garages, basements and other details. You should correct those mistakes in your appeal.

A quick Google search using your county’s name and “property records” should get you to the right place. Some online search systems are finicky and you have to make sure you get your street number and name exactly right.

Tell the assessors what they don’t know.

While your county assessor has a record of your property, there are things they don’t know. Typically, these are issues that decrease the value but aren’t obvious on the outside. For example, a sinking basement or a crack in the foundation should be reported.

Is your kitchen filled with 1980s-era appliances, floors, countertops and cabinets? Document that for the appeal.

If the houses across the street all have better views of the Rocky Mountains yet your property was given the same value, point that out.

But don’t document every single flaw.

Every house has flaws and needs minor repairs. So 15-page narratives that document every scratch and dent won’t get you far. They just take up valuable time and slow down the appeals process for everyone.

Analyze comparable sales.

You can pick out three to five comparable home sales to make your case. But there’s also no need to create elaborate spreadsheets with data from comparable sales across the county. The assessors already have that information and will use the same data when evaluating your appeal.

If you have questions, make a phone call.

Every county assessor says they are available to answer questions about property values and the appeals process. Don’t hesitate to call.

You also can consult real estate brokers to ask about fair values for your home. Don’t forget, though, that you’re looking at what your house was worth in June 2022.

Be patient.

Assessors are being inundated with phone calls and emails about property valuations. Appeals are being filed in record numbers. Screaming and insulting the assessor’s employees won’t help things. Kindness goes a long way.

Responses will arrive by June 30 or Aug. 15, depending on where you live.

Most county assessors, including in Arapahoe County, have until June 30 to respond to appeals. But multiple large metro counties — including Adams, Boulder, Denver, Douglas and Jefferson counties — are on an extended calendar and have until Aug. 15.

If you don’t like the answer, appeal again.

There’s almost always an avenue for taking a complaint further up the government chain.

For property value assessments in Colorado, the next step is your county Board of Equalization. In most counties, those boards start holding hearings in July and August.

The larger counties that operate on an extended calendar hold their Board of Equalization hearings in September and October.

During these hearings, professional real estate brokers and appraisers hear arguments as to why a property’s value should be set at a specific price. The assessor’s office and the homeowner present evidence. Then that professional, who is hired by the county, makes a decision.

If you disagree with that decision, you can take your case to the Colorado Board of Assessment Appeals, your county’s district court or to binding arbitration.

It’s still too early to know exactly how much these massive value increases will impact your tax bill.

For some folks, knowing how much their taxes will go up and how much they could potentially save by lowering their new valuation will determine whether they make the time and effort to appeal. But the assessed value of your home is just one piece of the equation used to calculate your property taxes.

The Colorado General Assembly passed a bill earlier this month that aims to soften the tax blow from the increased property values. But a conservative group filed a lawsuit on Monday seeking to block the measure, so that is not guaranteed relief.

Also, everyone’s property is taxed by multiple local taxing authorities. There are cities and towns, counties, fire districts, water districts, library districts, metro districts and countless other entities that charge you taxes. In Douglas County alone there are 315 taxing districts, although not every property owner pays into all 315 systems.

Those taxing authorities won’t set their tax rates — known as a mill levy — until later this year, and tax bills will go out in January. If you’re concerned about your property taxes, you can call those elected officials and tell them they should lower their levies.

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