Estimating market value in a crazy market

[Rob C.]

I'm trying to gauge the market value of a property that I have under contract. The difficulty is that the only comps in the same neighborhood over the past few years have been foreclosures & short sales. And the prices vary wildly!

Below I've listed the details of the property I have under contract, along with the comps I've been able to scrounge up online and with the help of my agent. I'm interested in hearing the opinions of the biggerpockets community regarding what its fair market value might be. I also think using a concrete example like this will help everyone (particularly rookies like me) get a feel for how others in the biggerpockets community analyze market value.

Property I have under contract:
http://www.redfin.com/GA/Lawrenceville/1964-Watercrest-Cir-30043/home/24887058
It's an estate sale. Under contract at $82,000. Needs about 15k in cosmetic work

Other comps on the market:
1) http://www.redfin.com/GA/Lawrenceville/1694-Watercrest-Cir-30043/home/24975674. under contract for $81,000. needs some cosmetic work as well (not sure how much)

2) http://www.redfin.com/GA/Lawrenceville/2054-Watercrest-Cir-30043/home/25095074 - listed at $94,900 (though I'm not sure what it's under contract at). upgraded bathrooms. good condition for the most part, but carpeting could be replaced in certain areas. Half of garage appears to have started partial conversion to 1 bed and 1 bath. Framing and plumbing, but no walls. Water heater and HVAC displaced to locations right next to where the cars would park (i.e. not to code)

Previous sales:
1) http://www.zillow.com/homedetails/1394-Watercrest-Cir-Lawrenceville-GA-30043/14803781_zpid/
Supposedly move-in ready according to description. Sold for $79,000.
2) http://www.zillow.com/homedetails/381-Fountainmist-Trl-Lawrenceville-GA-30043/14803863_zpid/
on adjacent street. sold 6 months ago for $95000
3) http://www.zillow.com/homedetails/1524-Watercrest-Cir-Lawrenceville-GA-30043/14803791_zpid/
500 sq ft smaller, but supposedly in "perfect condition" according to the ad. Short sale that sold 5 months ago for 40,000!
4) http://www.zillow.com/homedetails/420-Fountainmist-Trl-Lawrenceville-GA-30043/14803859_zpid/
on adjacent street. sold back in March for $38000!!

Thanks, Rob