For your purposes, it would be best to visit a local brokerage office, ask to speak with one of the realtors there and give them the details of your home. Example: when your home was built, square footage, lot size, number of bedrooms, bathrooms, whether your home is updated or not, etc. It should take a realtor about 3 minutes to find some homes in your area that have recently sold and give you the sold prices. This will tell you about how much your home will sell for.
You can also invite realtors to your home for a more thorough analysis BUT BEWARE - realtors who visit you at home are interested in having you sign a listing contract. They will convince you to sell now. If you visit them at their office, the pressure to sign a contract is not as great because you can easily walk out of the office and go home. It's a lot harder to force a realtor out of your own house.