The fact that there is not much appreciation can be okay, as long as you have healthy cash flow.

Even more important than the PM you use (so long as you use a licensed and established PM) is the neighborhood you buy in.

And, if I use my profits to roll back in to the business to improve properties, do I pay taxes on those gains, and then put the cash back in, and as long as the house/land is sold within 2020, be able to write off the money I put back in the company?

Even one yielding a conservative 6-10% IRR is totally fine by me as long as I can defer the tax. 

In other words, if a seller is open to hard money, they should be open to a portfolio loan as well, as long as it can close quickly (meeting the #1 requirement).As for whether you need one or more POF, that's up to the lender. 

So as long as your credit score/DTI are good you shouldn’t have an issue

Usually this will happen quickly, so long as you are a generally credit-healthy individual.

As long as property appreciation stays under rent cap it might not kill their rental market.Expensive properties with slow rent rate increases and rent control?

As long as you get a contract lower than the MAO, you should be able to sell it at or near that # and you won't need to negotiate your fee with your buyer.

Very minimal stuff can be done by the homeowner, as long as you get certified by taking an online test.