Run the comps to see if you would profit from the sale, keeping in mind that you should qualify for nontaxable capital gains.

The seller’s agent will have to vet the potential buyer on behalf of the seller and if the potential buyer is qualified, show him the property.

if the answer is no.. then please keep in mind this will be next to impossible for you go get unless your financially strong enough to walk in the local bank and borrow from them. no HML is going to loan that kind of money on new construction for someone with no track record.UNLESS you put in a huge amount of cash.. up front. so were We see all these folks getting scammed is they don't realize they really don't qualify for financing.. there is some notion running around that HML are just equity lenders they are not.. they are experience lenders IE how many have you done.. first time borrower VERY short leash. so you have the scammers saying no problem  the bigger the loan the bigger up front fee they hit you with and never fund.If you have the ability to go on American Greed website.. look up the episode on Remington financial.. they were the mother of the pump and dump Due diligence scams.. 

Now 5 years from now , you get married and want to buy a house , you will have a hard time qualifying , because you still have a mortgage in your name .Dont do it . 

I don't think a Seagrams 7 qualifies as a bourbon or scotch, barely even a whiskey........ :-)

Given that she is a CONSUMER it may be difficult qualify her ABILITY to REPAY.  

It will sit on their credit and prevent them from qualifying for a loan or taking advantage of another landlord.

I highly recommend a well-qualified REALTOR who works with investors and knows how to help you best.7.

I would recommend talking to a Qualified Intermediary for specific advice.

With that, based on your numbers, I think you should go for a HELOC and I think you should easily qualify for up to $700K as HELOC limit.