The seller, who inherited the property, was motivated to sell and move on.

Given that the house is paid off but has $27K in back taxes, you could offer to cover those taxes upfront in exchange for favorable terms on the remaining balance—like low (or no) down payment, and small monthly payments.You could also negotiate for a subject-to deal where you take over the property subject to the taxes, while still securing control of the property for your BRRRR strategy.

One option is to have the buyer use a loan to buy out your existing mortgage, and then you can carry a second lien on the property for the remaining balance.

However, if a unit remains vacant, I recommend setting rent just above the market average — in this case, around $1,800 as you've identified.

So for the example above, the payment would remain the same until maturity but you'd also be paying interest on funds that you haven't used yet. 

It's already headed there.And that's while we operate at all-time highs for travel in an economy where travel demand has remained at peak. 

This motivates me to start talking to corporate tenants! 

I've been in contact with them and some of the replies have been "unfortunately it can be slow depending on the area and the time of year" and "the timeline for how long a property remains on the market can vary, as it depends on the specific situation", in other words some pretty vague answers.

Personally, I’m seeing a lot of interest in fix-and-flip projects and long-term rentals, but financing remains a key challenge for many.

The forced gain or appreciation and straightline 1250 depreciation are usually more than enough to motivate someone to contemplate a 1031.