I really can't point you in a direction as to how you can get some semblance of accuracy.  

I found the cost to be to high to make sense especially since we would need a GC to mange it (we directly manage our local construction projects)

Typical investment company like Fidelity, Charles Schwab will not handle self directed 401K.

@Michael Lang I love honesty and direct communication.  

It's sad...but making me try to re-allocate my time and resources so that I can do my own direct marketing more effectively. 

You mention the owner has paid $70k on the mortgage but that isn't a number that matters (since who knows what interest rate he's on or if he's made any extra payments), what matters is what the outstanding balance is on the mortgage and can you offer them a purchase price that is A) Fair to the owner, B) Helps them sell with some amount of equity and C) Gives you room that it financially makes sense.The numbers change based on if you want to flip it or rent it, making the question "does it make sense" different based on the direction you choose.In short, I have no idea how much I would offer...

Look into getting an FHA loan, talk to a lender and see what you might be missing to qualify.. might need a little more income or more credit, a good lender will point you in the right direction if you couldn't immediately qualify that is. 

But would have me treading very lightly when it comes time to make an offer.

Search for @Kweillin Gordon on here and see if he can point you in the right direction. 

I may be able to point you in the right direction.