HELP! Feeling like i am in a foreign land!

[Jackie Boyd]

I have a potential seller for a wholesale deal. Right now I feel like I am in a country where I don't know the language but just a few words! So at the risk of sounding dumb, I am going to get out all my potentially ignorant sounding questions here! So the house is a 3 bed room, 1 1/2 baths, a little bit over 1700 sq ft. The house was completely remodeled in 2010. They were asking 150K for the house. First question where is the best place to find the actual value of the home? I went to zillow and I know this might be the amateur way of looking up a potential estimate but it estimated the house at about 93K. I was going to talk with them if they were willing to sell the house for whatever they have left on the mortgage. Is that the right approach? I am so clueless as to what number I should offer them. I know I could potentially get turned down and that is ok with me. I just need to know how to figure out the right number to offer and know that when I present it to an investor it will make sense to them also. As you can tell i am so clueless as to what I am doing and I am pretty much just throwing bunches in the dark until I hit something lol! Even if someone could give me a list of things to make sure I cover, that would be helpful. GRACIAS!