As I'm sure you're well aware, the small multifamily space in metro ATL is competitive despite current interest rates. 

Attend your local REI meet-ups and try to find someone who is currently house-hacking or has house-hacked in the past to learn from their experience.

Is this a 2 bedroom apartment that is currently being leased (in the eyes of the CHA) as a 1 bedroom apartment?

Major brands like Ritz Carlton and Waldorf Astoria are currently developing property there, where they have traditionally developed in Miami, Fort Laud, and Palm Beach. 

Simply gifting him half the property now wouldn’t immediately allow him to claim the exclusion without fulfilling this residency requirement, I don't believe.One thought would be to use a HELOC to pull just enough equity out of the current home and use it to buy a smaller home, or at least the down payment.

Find a partner, find co-workers/friends/relatives you wouldn’t mind living with, find a property you can buy for less than your current rent.

Seems like a good idea in theory maybe not in practice. 

Find Brandon's videos on YouTube for the "four square" method of analyzing homes and practice.

Your tenants obligation was to pay you on Jan 1, so it doesn't matter if they paid someone else they still owe you...obviously details re: notice and dates all come into play here and from a practical perspective I'd work with the tenant and not move to evict over this.

It can make leasing a bit harder since you will have more vacancy when those come do but it will all be in peak season.With respect to the hiring decision, you would need to hire someone to replace you (perform the same functions you currently perform) so that you continue to work up the ladder (spending more time on higher value tasks).