You could start an HVAC company that does installs and/or does trouble shooting when it's peak season.

He is a CPA in Cincinnati, although since it is still busy season for him he might not be freed up for a few months.

My mom who is older than yours only gets a government pension, but she owns her house.

The deal is a short term rental in Florida so the returns are very seasonal.

I'll probably connect with you when I'm a bit more seasoned. 

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As long as the numbers work, locations are good, I'd rather have newer than older.

Renters are notorious for harder wear and tear on a house than owners, so rental homes require more energy from the owner or manager to upkeep.You need to schedule seasonal maintenance to keep appliances functioning, gutters from overflowing and to check in with your tenants.

The property's estimated After Repair Value (ARV) is around $525,000, and my total investment stands at $350,000.This is my first venture into a property with 4+ units, though I consider myself a seasoned investor in other real estate ventures.

Not sure what you mean; this is very common in older homes.