The AC unit I'll admit is not brand new, however it was in working order and has been serviced regularly to maintain it and make sure that it is not in disrepair.

There are still tons of people who will buy or rent within an COA/HOA because they like that the who community will be maintained to a certain standard, the cost of shared amenities is spread out, there is a management company who will handle all the maintenance items on the exterior of the unit for you and usually budgets for replacement of items.The cons of a COA/HOA is that they require an application/approval process. 

I've been a full time RE investor in Columbus for 3 years now focusing mainly on rehabbing & flipping homes, turnkey rentals, wholesaling, and building a rental portfolio so feel free to reach out with any questions.  

If so, how much management company time will have to be devoted to setting up and maintaining electronic mortgage paying accounts for all of these customers?

Being 23, I'm really trying to figure my life out now that I have graduated lol There is no need to take the risk of starting a full time real estate career without doing some deals first.It makes a lot more sense (risk-wise and financially) to have a full time job/career while doing real estate on the side.

Additionally, item (2) in the estoppel states that the existing lease is maintained in full force, and the tenant write "N/A" to any modification, exceptions, etc...Its my understanding I'm required to uphold the lease terms.Any advise is helpful!

Or the property's ability to maintain value in a downturn?

Yes, there is something to be said about preventing repetition and maintaining continuity, but to me that is outweighed by not having to scroll and scroll to get to the last post and scrolling is much worse with the redesign. 

We maintain a document of potential client details so we know who is interested, what they are looking for, etc.

Otherwise, you do not need to maintain an accredited investor status.