There are three FREE ways to find out in Washington County: County Records, Tax Records & Realtors.
Many Realtors (me included) will provide you with a free market analysis that is specific to your area & homes similar to yours (or the one you are looking to buy). This service is usually offered FREE with no obligation, but expect to hear a pitch about the benefits of listing your home with that Realtor (it is only natural... or we wouldn't be good Realtors!) Whoever you hire, make sure they go into detail in their comparative market analysis (CMAs) so they are as accurate as possible.
If I were you, I'd contact two or three Realtors have have them present this information to you & then select the one who is GREAT to market your property. If none of them are GREAT, hire three more! This is FREE. Just let them know that you've also talked with a few others.
If you go to the county court house, you can look through the records to find homes that have recently sold. This is affective, but it takes a while.
If you have access to tax records, you can also check there.
Realtors will use the two sources above along with the MLS system to find all the necessary info to price your property.
The other way is to hire an appraiser. The cost varies but it is the one you can count on & say, "My home appraised for ___." You can't say that with a broker's opinion of market value (CMA).
If you have any questions at all, please feel free to contact me. Ray@theRayTeam.biz or my cell phone: (479) 422 - 2279
Thanks for using Trulia & posting your question. I look forward to hearing from you.