Where is the property, how much do you expect to pay for it, does it have split utilities, require substantial capital expenditures? 

SFHs in my market sell within hours with multiple offers all substantially over list price.

You’ll find an old house (~1980 or older), outdated, likely with problems, smallish (under 1500sqft), in need of substantial rehab.

@Frank Agyeman-Duah your realtor has a financial incentive to close the deal despite this substantial problem.

These are highly unlikely to influence the tenant's ability to pay me.

My list of favorites for those categories areHow to win Friends and Influence PeopleEat That Frog4-Hour Work WeekThe One ThingIf you haven't read it yet, I think you should first pick up Rich Dad Poor Dad

(You should try reading the book "How to win friends and influence people". 

To take a theft loss for tax purposes we generally need to have no prospect of recovery, and exhaust all other avenues of collection.Your points are good ones and I always recommend building the paper trail (substantiation) for tax. 

I also have access to a relatively substantial amount of HELOC money, we keep it as a safety net, but would it be wiser to draw that down and use that for the down payment?   

The substantial upswing in demand is driven by a need for indoor and outdoor space met by record lo w mortgage rates and a wave of millennials who were on the verge of buying — all competing for fewer and fewer homes on the market.