any advice on how to find comps besides zillow trulia etc .  

 i have a house im trying to get under contract the sites say 150k average the seller says its worth 290k but wants no less than 200k i know he bluffing ......but he called me from a mail i sent a month ago .... how can i get a correct price point on comps .... its a pretty house 5bdrm 4 bth around 1600 sqft which is small i know but he also owes 5k in back taxes...... thanks guys any help or point me in the right direction would be of great service  

Get similar homes that have sold nearby and show the seller, and explain your process and show why nobody will pay ARV- repair costs for the home

realtor.com is a little more in depth than the two you mentioned in the original post. I'm just starting out and doing some mock type searching on these sites and found that one to be a bit more helpful, hope that helps.  I'll be following this thread, thank you for posting 

@Mike Ross

You can still use zillow, trulia, realtor.com, just use recently solds to figure out your ARV, not the "zestimate" or whatever. Not the most accurate data, but if you have nothing else it can do the job. So once you have some houses you can go to him and say "look, these sold for $x in better shape (or bigger, or whatever you can say) I can only offer you $x because I want to make a fair profit and I can't do that if I pay $x, put $x into it, have $x amount of holding cost, pay the the realtors 6%, and so on.."

I was going to say to move on because he doesn't sound motivated but if he owes taxes, maybe he is.