I acquired a home once and put a year into making it habitable again also but didn't add the value percentage you achieved. 

You might do yourself more harm than good especially if you they perceive what you're doing as "used car salesmany". 

Choose carefully so that you don't spend more on making it habitable, than the property would be worth after the repair.

No harm in seeing what they offer I guess, but I wouldn't sign up for anything. 

Conventional can work, but remember that the bank will be hesitant to lend if the property doesn't look habitable. 

In 7 Habits of Highly Effective People Stephen Covey talks about "sharpening the saw." 

In other words, have them in tip top shape (at least reasonably habitable) so your lender appraisals come in as high as possible. 

Have you changed your habits in food supplies available to your guests?

You of course will probably need to pay the property taxes, keep insurance on it since you own it of record and hope the Borrower keeps it in somewhat habitable condition.Then, assuming you win, you get clear title to the property. 

The good thing about a HELOC is if you don't use the money, no harm, no foul.