The best thing to do with any domain name is to get a
professional appraisal so at least you have a perspective
on the value.

Be sure it is from a reputable company or it's worthless.
Don't get caught up in paying too much for a domain name appraisal and especially don't use any of those fly by night scammer companies.

Below is a really good option for yourself to know what you have without spending allot of money:

Express Domain Appraisals
Based on 5 critical factors
Results in 2 hours or less
Appraisal displayed via a secure Web page - Just $ 4.99 per name.

Below is a very good option for yourself to know and to show a buyer what current market value is in reality without spending allot of money:
(Others charge $30.00, (in my oponion TOO MUCH!), for this type of certification)
This is like a certified real estate appraisal you can take to the bank.

Certified Domain Appraisals
In-Depth Analysis of 5 Industry Standards
Results in 2 business days or less
Appraisal displayed via a secure Web page - Just $14.99 per name.

Don't be fooled out there, one of these appraisals is all you'll ever really need.

If you want an appraisal from a reliable source here is a
really good reliable and industry wide respected source:
Here is the link For ACCURATE APPRAISALS

THE BEST APPRAISALS YOU CAN GET FOR THE BUCKS.