Zillow automatically advertises your entry in Apartments.com, Hotpads.com and a third online apartment app that escapes me at the moment.  

Gwinnett county seems to have a high cost to entry right now.

Check your lease and see what is says about non-entry.

didnt read everything others have said. but run back to your w-2 jobs as soon as possible. like call them today and ask for  them to take you  back maybe even say please. then pull  heloc on your properties and go buy more rental. you can buy them with out a w-2 unless you pay cash. dont want to be a cook for 16 this is a great time to switch jobs and pretty much every one is willing to pay you $20 an hour as long as you negotiate there is no competition in the job market right now. so best time to switch at great entry point. your cash flow seems great on  the other places get a few more then quite your day job if you want. and if you meant you want to be an agent run away. the only career that is probably currently saturated is real estate agent every one became an agent last year

Leave him a letter asking him to provide notice of entry?  

Promptly after the property has been treated go seal all of the located points of entry with a plaster/foam. 

I'm fascinated by the overall real estate market disruption from the pandemic (influx of people/govt manipulation with eviction moratoriums, etc.) and now the further disruption in our local market from hedge funds swarming the entry level SFR market. 

What I would recommend is look for a market that low cost of entry for a 3/2/2 (3 bed, 2 bath, 2 car garage).

Are there any regulations or barriers to entry we should be aware of ?

I felt like turnkey was a good entry point to make an investment and start learning more about the process so I went this route for my first investment (see post below).