I imagine plenty of people buy them - the rules will be pretty much the same - you have a minimum you'll accept for it - buyers will have a maximum they'll spend on it hopefully the two will match!
I'am new in this domaining buisness, but I have a portfolio of several domain names for now. I'm trying to sell those, on my own, but it is not easy task. Can you give me an advice or recommend me some broker?
It all depends on the quality of the domain. No point using a broker or going through sedo and paying fees if the domain is crap. Listing it on this site is free but you need to build up some posts and get "established" before you can sell - that's a good thing because other users can see your posts and make a judgement on how reliable and honest you are before doing business with you.