Who is entering the payments on the tenant's ledger?

Cast a wide net using various methods.

Simple 4 page executed contract provided for purchase money mortgage (pmm), seller financing $375k @ 4%, repayment monthly amortized 30 year, 15 yr balloon, no pre-payment penalty.

House hacking is an excellent way to get started as you can take advantage of the lower down payment options.

Perhaps a good method to start with is getting to know a recommended local RE attorney through referrals that has experience in the area in which you're looking to invest, be that now or in the future and have legal contracts prepared to make sure the capital you invest is protected.

Here are some things to consider:Most of Cityfheps are coming directly from the shelter and with my experience it’s hard to vet them since they want to be out and you do not consider income and credit. in general they are not used to keep an apartment (recycling, cleaning etc…) since they do not have any responsibility at the shelter and some of them stay there for years.The city will mail you the payment and usually it’s twice a month.

In Louisville I would do the (BOMSTSLO) Method.

What is the best way to make the payments to the seller?

As I understand it, it's the loan amount that requires the down payment not the potential market value of the property.  

Your payments will be lower than a new loan.