Is this market accessible for the average investor in the UK, or is it exclusively banks and hedge funds who buy/sell these sorts of instruments?

there is a lot of competition - you're going to be up against both other low-budget operations and also high-budget, national operations. 

If this is your tenant base then your rent roll may be high but your probability of actually collecting that rent roll number is low.

Low cost of living, strong job markets, and strong monthly rental growth in both these states have a lot to do with it too.

He thinks they can rent each room out for $800 for a total of $3200/monthHe has offered 10% for me to manage the renting of the rooms to the tenants and to take care of the lawn and snow.This initially sounds low to me. 

I had initially reached out to Trophy Point for funds to help acquire the deal.

To your question in the post's title: It's got to beat low risk investing, such as treasury bills.

Depending on the demographics of the area, I've found that Home Depot/Lowes is fine for just about anything going in a regular rental.One must consider return on investment and buying fancy custom cabinets won't yield much if any more rent that box store shaker cabinets, especially in a duplex.Get some decent cabinets and a good countertop and you should be good to go.

Check in with my lender of 20+ years @Joseph Chiofalo he’s helped my buyers coordinate cash out transactions and low ltv down payments on acquisitions recently.

My costs might have been high and my rents too low so don't take my one data point as the answer without doing your own research.