Listing, applications/screening, leases, online rent collection, and maintenance tracking? 

There are limits on them and if your policy only covers 4 rentals, but you plan on acquiring more, you'll need another umbrella policy for the additional units. 

I buy and rent homes most of the time and I would like my 23 year old son to learn how to buy with his limited income.

Contents (Personal Property): most homeowners policies give a set % of the Building limit for Contents.

Given that the parish is a hassle, I'm leaning towards the limited hassle of a tenant that can be evicted over non-payment rather than dealing with a finicky government entity that can be slow and fails inspections for silly reasons rather than actual issues. 

My point for you is that buying a single home and using all of your money to do it could limit your growth.

I feel like your ability to add value or raise rents would be limited by the other units within that same HOA.

Do a full loan application, let them pull credit (you have three scores they will use and the model run for mortgage purposes is typically a little lower than what you are viewing).

If your doing it in the city limits just find the right website and it should have enough info to give you an idea.

You can have many carriers on your tower but you are limited to the carriers that operate in your market.