In terms of your grandfather living there as long as he's not the owner having a dwelling fire/rental property insurance policy is appropriate.As @Greg Scott pointed out he should have a renters insurance policy whether or not he's actually paying rent.In terms of liability coverage, that depends on what you have to protect so there's no one-size fits all approach.

This is my first time as a home owner...AKA Please be kind!

Tenants pay for gas and electric, owner pays for water.

The house is going to dampen the value of the park as a singular investment and subsequently the park is going to dampen the value of the house. 

Jerrylls site style performance: The design style he created on top of the Carrot system consistently is in the top group of sites when we pull a list of the top 100 highest converting motivated house seller sites on our system. 

Additional information: I do not plan to keep this house forever.

I'm working on a short plat and will be building another house on the new lot. 

A building with to high STR non owner occupancy doesn't appreciate as buyers cannot get conventional or jumbo financing in the future.

Antonia Noori Farzan recently wrote a wonderful article in the Providence Journal about rooming houses.

Hello  my name is dozar  from chambersburg pa , I own a duplex  and plan to buy one property each year  for 10 years through house hacking method.