You want to win any chance to convince a person to click your ad.2- The ad is targeting the wrong keyword.

That way you're not locked into the deal without getting an estimate and if the rehab budget comes in higher than $65k you can easily walk away- make sure the assignment says EMD is refundable if you do decide to walk.The 70% rule is a great rule of thumb.

Lenders (maybe even the state), wanted to give locals a chance to purchase their home.I dont see a problem with investors needing to come in with 20% down.

Cash Purchase Price: $43k, Renovation & other fees: $66k, Estimated closing: $13k.

The property owners will be asking $170k, but it needs an estimated $60-80k in repairs.

You won't get cash flow while you live there, but you'll have a much larger selection to offer on, giving you higher chances of finding something that's actually a deal from an ROI standpoint. 

Does anyone have rule of thumb cost estimates for this kind of work?

There's a very good chance the issue(s) you face have already been discussed and answered.Ask questions in the appropriate forum.

I was wondering if anyone would be able to give advice on if there was a chance of getting a HELOC in my current situation.  

Your chances of winning are close to zero.