To qualify for a loan, focus on having a credit score of at least 620 (or 580 for FHA loans), keeping your total monthly debt under 43% of your income, and saving enough for a down payment and closing costs—about 5-10% of the home's price in total.

(Also fill out your profile with this same info)Looking forward to hearing more! 

Tenants save money when using a shared meter, so there's plenty of room for error when calculating how to distribute the charges.

Could you provide more info?

I'll PM you the info.

Typically these people are really forthcoming with info and can tell you.

Some info: -The 'investment property' is worth ~$650K and is paid off.

I would still need to subscribe to a streaming service for cable tv, so cost savings wouldnt be much (or a wash), but otherwise it seems like it might be a viable alternative?

As others have said, the best thing your son can do is run far from this deal, buckle down, save his pennies (he probably already is doing this), house-hack, and improve a property with sweat, hard work, developing a DIY skillset, and self-managing tenants. 

Seller Pre-Sale Financing: Consider selling the tenant-occupied property "as-is" now to an investor, perhaps at a slight discount, which could save time and eliminate renovation costs.