I'd also add to that that you are paying a 20% withholding tax on gross rental income. 

Here's a bit more in detail about how rates are calculated for DSCR loans:1.

You can also expect increasing HOA fees, and there may be some problems renting a property inside a difficult.You don't have any experience, prices are at an all-time high, and rates are also high. 

So the question becomes based on their individual and personal tax situation what is the estimated tax burden they'd save? 

401K loan is capped at 50K and with withdrawal, you have 10% penalty and tax implications.

It’s definitely smart to evaluate the tax and cost implications of your funding options.

Instead of evicting them, i was thinking is there some way that I could rent it back to him for very cheap (mainly to cover just the taxes/ insurance) ie 2k a year rather than the going rate of 2k a month for similar properties.

@Nicole GrazianoI recommend that you have a consultation with a real estate tax accountant regarding your taxes.Bigger Pockets is a great place to find a real estate tax accountant. 

It's no different than their 2-year, low interest rate teaser houses.

Assuming property taxes + insurance added don't go above $1,100 total, you could maybe make this work.