QUESTION: Sub-To Mortgage and HELOC

[Evan Kline]

I have a sub-to deal I'm closing at the end of this week (hopefully! not counting my chicks until they hatch). 

Seller was about to foreclose, I offered to come in and buy the home, take over mortgage subject-to, no cash paid to seller. Helped her out of a tough situation (she also owns another home she lives in with her husband, just decided to let this one go), and I'm getting a home run deal.

Deal #'s

2/1, 900sqft, B+ neighborhood (I own three other properties within 3 blocks)

Mortgage subject to: $96k 

Past due payments: $10k

HELOC: $25k

ARV: If I just fix up the current sqft, ~$250k. There's an attic and basement that are finishable and I could double the sqft, add 1-2 bedrooms and a bath, which would bump up ARV to $400k+

My question is: would you take over the HELOC or would you pay it off? I called the HELOC lender and they were cool with me "working out a deal" with the current owner instead of paying it off. My worry is, the seller isn't great with money (hence the foreclosure) and I'm slightly worried she may go in and try and withdraw from the HELOC if it's still in her name.

But on the flip side I can slide into this deal with only $10k to get the current mortgage up to speed. House needs about $100k reno and I already have a hard money lender lined up. 

What are yall's thoughts?