Tens of thousands of homeowners in the Sacramento area are headed into another year of an expensive tax cycle - one of paying those hefty property tax bills that help fuel government operations.

For those who believe their property assessments are too high, this is also the time of year owners can try to do something about it. The windows for challenging your property tax assessment are about to close in Placer, Yolo, El Dorado and Sacramento counties.

Following is a step-by-step guide on how to get started. All it takes is a little homework, some paperwork, patience and basic analysis.

Your first question: Is your home's assessed value in line with sales of comparable properties in your neighborhood? Or is it too high?

To find out, look at sales of homes with similar amenities, square footage, bedrooms and lot sizes in your neighborhood. County assessors tie their valuations to Jan. 1, 2012, so focus mainly on sales from Oct. 1, 2011, through March 31, 2012.

Online resources are useful for this. Among them: Visit sacbee.com/homesales, where you can search by size, price, location and date of sales. Or check out redfin.com or zillow.com for listings of home sales by date in your neighborhood.

A tax refresher note: If your property's "net assessed value" is $250,000, that's the number you'll work with for these comparisons. Your annual tax bill will be 1 percent of that amount, or $2,500, excluding direct levies for community financing districts and the like.

Now you're ready to get started.

Placer County

Placer County Assessor's officials mail notices of assessments each July. The county has an excellent site to help navigate the process of challenging your assessment.

Visit placer.ca.gov and choose Assessor from the drop-down Departments menu on the right. From there, go to In the Spotlight at the center of the page and click Reducing Your Assessed Value.

The graphic explains how Proposition 13 governs increased property assessments once they are lowered because of market conditions.

The deadline to ask for the free voluntary review of your assessed value is Dec. 31.

But keep in mind that the first installment of your property tax bill is delinquent after Dec. 10.

Most importantly, if you wish to appeal your assessment outright, you must submit the paperwork to the clerk of the Assessment Appeals Board no later than Sept. 17. The cost is $35. So if you think you're going to need to file an appeal, don't wait for the review.

Questions? Call the county assessor's office at (530) 889-4300.

Yolo County

Yolo County links to homeowners' current assessed values (for 2012-13) from its website, yolocounty.org. On the right, click Prop. Tax/Parcel #. Be sure to have your parcel number handy. It's listed on any past or current property tax bill.

To discuss the assessment with the assessor's staff, call (530) 666-8135. For an informal review, visit the Yolo County Assessor's Forms page. The form you'll want is near the bottom of the page, labeled Residential/Agricultural Informal Review.

Still want to proceed to a formal appeal? Return to yolocounty.org and choose Assessment Appeals under the Hot Topics menu.

You must file the application no later than Nov. 30. The filing fee is $45 per appeal.

El Dorado County

Residents who want to discuss their property tax assessments with the assessor's staff can call the office at (530) 621-5719.

To appeal, file forms with the county Assessment Appeals Board by Nov. 30. For an application, call (530) 621-5654 or visit the county Board of Supervisors' website to download.

Cost to file is $30.

Sacramento County

Property tax bills will be mailed to homeowners in Sacramento County in October.

If you don't want to wait until October to see your 2012-13 assessment - the assessment used to calculate the next property tax payment -- go to assessor.saccounty.net and choose parcel viewer.

Enter your street number and name and look for the Net Assessed Value listed below your address and parcel number.

If you don't believe the net assessed value is a good reflection of sales of comparable homes in your neighborhood at the start of this year, you can ask the county for an informal review of your assessment. It's free.

Call (916) 875-0700 or visit assessor.saccounty.net and print out the Request for Assessor Review, fill it out and mail or fax it to the county.

The assessor, in response, can examine a specific property closely, zeroing in on a specific street or house or area. The assessor's staff may adjust the appraisal or decline to do so.

The process for establishing residential valuations is not foolproof. The assessor uses "mass appraisal techniques" that account for home sizes and other attributes within neighborhoods.

If you're unhappy with the outcome of the informal review, you should go next to the Sacramento County Assessment Appeals Board at sccob.saccounty.net.

Choose the Assessment Appeals Board link to see all the forms and steps you'll need. The cost to file is $30.

For this you'll want supporting information. Go back to the online resources mentioned above to provide specifics for your application.

The appeals filing period closes at 5 p.m. Nov. 30 for the current tax year. Most people wait until November to file their claims. By then, the county assessor's office is swamped. So it's a good idea to get ahead of the pack.

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