People sell properties like this all the time for many many reasons. Freeing up money, getting out of real estate, divorce settlement, bankruptcy, etc.
Knowing the sellers "why" is great but if you cant use it for leverage in negotiations than all you can do is cover yourself in the due dili phase. Do you inspections, run comps, talk to your agent about everything, bring a contractor through, and most importantly run worst case scenario numbers....if that number is something you can stomach then you are good to go.
If the numbers work, go for it. If they dont, put in an offer for the number that makes sense to you. If they dont take it then move on.
Trust, but verify everything the seller says. Sellers fudge numbers, property conditions, and their stories all the time. Take whatever they say with a grain of salt and do all of your homework on the property. Thats the only way to be sure of the property and what you are buying.
Hope that helps.