We eventually evicted her and since single families are not in our plan, we renovated and sold for our asking price of $250k 18 months after we purchased the property.

How much fair market rent I can charge.

I asked the contractors for a bid and they are all happy to come and walk thru the property free of charge.

We also see single family homes sell with tenants (more rare, but it does happen). 

I want to invest into a turnkey single family rental property. 

Petersburg and the surrounding areas, if this market is in a good spot to jump in, or if it might be better off to wait or go into single-family home investments?

You can build with equity and do more of a multifamily product not single family and do much better.

If my hunch that it is correct why would anyone be renting out a single family home at all in this area where homes are worth 1.5M and rent is just 4K?

You cannot really answer the question if an Investment is Cash flowing or NOT because it's not up to the INVESTMENT to cash flow.... it is the INVESTOR that cash flows the Property OR NOT.I see it time and time again, in every single book, guru or not.... the CHARACTERISTIC of Cash Flowing is NOT about the INVESTMENT... it's about the INVESTOR.This is why we need to focus on other things like Cap Rate and especially IRR.Here is another example with a Spreadsheet:You are thinking of buying 1 of 2 properties.

Instead of just pulling the trigger and buying a single family house, I thought of trying to sound proof the walls/ceilings.