Also the water heater was not working which also caused the HVAC not to work as it was on a heat pump system.

With your plan for a mini-split, the space should stay warm enough without it.

Quote from @Jacopo Iasiello: Hi Man, welcome here Thanks for the warm welcome Jacopo!

Your best bet is a property on water and sewer in a non HOA community and either convert the garage to an ADU or Build a separate ADU .

Water- Either check with neighbors, drill test well, or call me to Witch water to see if you have water on the ground. 

Added a new cistern for water and added a shop bathroom in addition to completing the apartment.

Each unit features 2 bedrooms and 1 bathroom, providing a total of 4 bedrooms and 2 bathrooms across 1,684 sq. ft. of heated living space.Key Features & Upgrades:New Roof for long-term durabilityFresh Exterior & Interior Paint for a modern and inviting lookNew Interior & Exterior Doors with updated locksets for added securityLuxury Vinyl Plank (LVP) Flooring throughout, combining style and durabilityFully Renovated Kitchens featuring brand-new cabinetry and quartz countertopsUpdated Bathrooms with new tiled tub surrounds, vanities, and toilet seatsNew Light Fixtures & Mini Blinds installed throughout the propertyComplete HVAC System Replacement for Unit 686 & New Condenser & A-coil for Unit 688Plumbing Upgrades including new water heaters, updated faucets, leak detection, and a cleanout drain installationSecurity & Hardware Updates with rekeyed locks, new smoke alarm batteries, door hardware, and cabinet adjustmentsNew Landscaping to enhance curb appealThis turnkey property is ideal for homeowners or investors seeking a low-maintenance, move-in-ready duplex in a prime Memphis location.

For a bathroom or kitchenette, the biggest factor is plumbing...if a water line is close, your in the money,  if not, costs jump.Best approach for now?

Now it takes weeks for them to respond and when they do its not a very warm engagement. 

(that policy was cancelled by the carrier and I will be getting a separate policy)2 hail damage to Tennessee property  and water damage due to storm (claim is in process) Another Tennessee property now has had a water pipe burst in the kitchen ceiling and flooded the whole house.