The other is in the low 500s but stated that this is due to a car accident totaling her car and is in litigation, so she is not paying on the loan. 

Because my equity is high, my ROE is low, but seems to make a boost on ROE if I payoff the remaining mortgage, which surprised me.

They’re relocating out of town and would like to sell by the beginning of the year.Here are the key details:Current rent: $1,850/month (tenant is month-to-month, wants to stay)Market rent estimate: $2,200–$2,350/monthTenant history: Has been there for about a year; was paying $2,150 at their prior rental, so an increase to $2,000+ should be manageable.Seller’s situation: They owe about $156,000 on the property and want to net around $100,000 after all taxes and fees.Existing mortgage rate: 3.5%Wholesaler offer: $287,000My position: I just bought a fixer-upper, so most of my cash is tied up, but I can access around $100,000 from a HELOC at 6.5% (15-year draw / 15-year repayment).Question:Is there a way to creatively structure a deal that allows me to leverage the seller’s existing low-interest mortgage — even though it’s not officially assumable?

If your vent/drain lines are PVC or ABS it's lower likelihood to crack but cast iron will crack over time.

Can anyone point me to free or low cost flipping training? 

Mailing letters and cold calling is effective, but its a volume play, expect to be uncertain of the likelihood of results most of the time, before that wears off. 

To lower audit potential a partnership LLC is 1 tenth the likelihood of IRS audit but you need a partner.

The other thing you could do is go to local networking events and be as helpful as possible to real estate investors in exchange for them showing you the ropes so you reduce the likelihood of mistakes.  

Newbies want lots of an agent's time, sending them potential properties, asking them to show them some of these properties, then writing low-ball offers unlikely to get accepted.Why would an agent working commission-only, want to waste their time on all this?

A great asset with low leverage and plenty of cash flow is not in need of pref equity.