I have never heard of a provider rejecting an investor.

You need to have consistent inventory and be a serious player to pull #1 off, assuming you are in a competitive market.

Farmland has proved to provide 10%+ returns. 

What I will do instead is give you some advice, make sure to do interviews with as many as turnkey providers as you can before deciding to work with one.

You will not receive any good pointers on valuation in these forums based on the information that's being provided.

I think is about relationships, after you reach out to all the wholesalers in your area in all the diverse ways possible and exposing yourself as an end-buyer on platforms like Facebook, you then start to vet out all these wholesalers and with time you'll see who the real players are and who the daisy-chainers are

If anyone could provide some insight into where the best areas and zip codes to invest would be and also any referrals to boots on the ground would be amazing!

Is there a website that I can go to to get one or I should just contact a HML to provide me a POF? 

You will never need to deal with the players again.

I saw a lot of people providing their deals there and they have several replies to buy the house.