When I/my son move out can I rent this unit to 2 college students (that are not related)?

Rates are similar, you can get interest only payments so your monthly payment is lower, and the loan doesn't go on your credit report so you can continue to invest in other properties without running into DTI issues.

Everything else I have read about them seems to be related to the US specifically and not mentioned at all amongst UK investors.

I'm kicking myself because I was having some technical issues with the format when I tried to update the lease document in MS Word.

2@Mary Chen, @Seo Hui Han I think your issues are going to be more with the lending than any 1031 restrictions. 

I asked him why, and he said after many days of review, he determined that after all the fees related to the new construction loan were factored in, the true return was less than the advertised pro-forma.  

To address this, we agreed that I would work in the business for six months to verify the financials, which so far align with his POS system.My main issue is that at 23, I don't have strong financials to get a conventional loan at 75% LTV with a ~7% rate, and the seller's lack of financials complicates bank approval.

This is not related to rental property.

There will be other large ticket issues that pop up as well as big things that will eventually need replaced like the roof, furnace, plumbing issues, etc.If you have enough properties for enough time the below or worse will eventually happen and repeat itself.

Most of the multi-family units in Jacksonville that I think are in an area that I would feel safe are in riverside/5 points or San Marco.The issue, I think, with Jacksonville is that the supple of Multi-family units is low which makes the pricepoint of them higher.