As you were advised above, we do not typically lend to even A Credit borrowers 100% financing. 

Rather, they prohibit the transfer of specific things, such as "services" or "extension of credit". 

Your only option is to offer tenant some money to leave, or reduce your purchase price by the amount you are losing (or ideally ask for a credit at closing).

I’m thinking I’ll look at the comps and compute a fair price based on those numbers instead of the current rent roll.

Basically, if your credit is good, go Conventional.  

. $20 and very comprehensive credit report and eviction, too.There are more expensive options but I'm fine with that one

I've done a fair amount of research into the benefits and drawbacks of different markets, but selecting one over the others feels like guesswork.

Should I hold the house for this buyer, given that the price she was asking for her own house looks quite reasonable, or should I put my house back on the market, assuming that the market in the neighborhood for that house is fairly brisk.

We pick it up from there and immediately deposit the rents into our business checking account at a credit union three blocks away.

You guys will have to obtain an EIN from IRS website to file the partnership website, fairly easy process.