TSYS as well .. credit cards and ach payments 

He had a opening cut through the wall below a window to install a thru the wall AC because with the window AC, he couldn't use the window.

If tenant pays by ACH, that's less than $1.50 per transaction. 

There was a lot of trouble doing ACH deposits into Fidelity and Schwab IRA accounts.

I would have him screened like everyone else, put the money in a separate bank account in his name with an ACH/bill pay to you each month for the rent due.  

The stage I am at now is deal analyzing (though I won’t be buying in the very near time) to start to build that muscle.

Train your tenants now.I have them deposit it directly into my bank account and they get a receipt, or use Bank ACH or Zelle.I don't have time to go to all my properties to get them to pay rent.

The main thing that I am interested in doing is online ACH rent payments. 

The portion paid by the tenant will be paid directly to you by them, and the Section 8 portion will be paid to you by the government (not sure if this comes in the form of an ACH transfer, a check in the mail, or something else).4) Adhere to the terms of the lease, and address any maintenance requests promptly in order to stay in HUD's good graces.5) Notify HUD if you plan to raise the rent. 

@Mark LiraWhat about setting up an ACH or other automatic payment that gives them slightly better rate if they sign up for it.