DSCR loans are based off of down payment, credit score and either actual or market rents so it helps to supercharge an investor's real estate goals and net worth.

Some companies call this a markup for managing the payment of utility bills.

Treat this property as a business and factor in all the associated expenses, including mortgage payments (if you pull a loan), maintenance, and potential vacancy periods.To simplify management and make this less of a hands-on job, I’d strongly recommend working with a property management company.

Then if/when another good deal comes up, you can approach a lender and look at leveraging either of the properties in order to fund the down payment of the new property.

I have enough saved for FHA loan down payment on a duplex up to 500k. 

How long have you owned these, and how much is rent vs the payment?

But my down payment 3 years ago is only 10% of the total price $42K.

The only slight red flag was that they only accepted payment via Venmo or wire transfer, but that's how I accepted payment when I was selling lead bundles, so I still thought it was worth a shot.

In my experience that's not actually the case at least in legitimate evictions for non-payment of rent or breach of another part of the lease.  

Tenants in lower Classes will have lower credit scores, which means higher chance of defaulting on their lease payments.