I have a Duplex I was doing a long BRRRR on.

This will obviously take more effort on your part but in the long run, the exercise will be a valuable lesson for future calculations.

In some cases, federal tax credits like those for low-income housing or economic development might also apply if the project aligns with certain goals.Instead of buying the land outright, developers often lease it from the tribe, which can reduce upfront costs and sometimes come with favorable lease terms.

call a few brokers and just see what their terms are.

Market rents in this area for those size units are closer to $1,100 (a little more, actually).Previous owners owned these spaces for a very long time, so their taxes were low and those rents were manageable for them.

Therefore, you don't need to use a 1031 exchange; you can take as long as you wish to find and then buy another property.The only exception is if there is debt on a property, in which case there will be some UBIT (Unrelated Business Income Tax) implications.

I'm not a property casualty agent (was a long time ago - now just life/health).

What should I consider about the purchase price, interest rate, and other terms? 

Understanding the terms, qualifications, and overall structure is crucial—after all, a loan is a loan, and knowing how to leverage it properly makes all the difference.As for Zillow, IMO, one should never use it for ARV.

If they gift it to you it's tax-free (as long as they're under the lifetime gift limit around 14 million) they may have to file a gift return though, but there won't be tax due.