Just a heads up: Windows Defender, the basic one installed on your personal computer, is good enough for personal usage.

I have a business google pixelbook, which doesn't use windows or mac os, so it is important that I have the ability to use some form of online access (remote login to pc or mac...or actual online software).  

Like someone else mentioned, doing a short term rental in a secluded basement that is very private and walled off is one thing, but sharing the same refrigerator, kitchen thermostat, etc. with a complete stranger seems like it will introduce more problems than what the money is actually worth.

This motel has 16 private rooms, 4 shared bathrooms,  1 kitchen and living room.

A cabin that in theory would have cash flowed positive almost $1K/month had the kitchen drain go through the crawl space and dump out about 4' away from the house.

For instance, one property seems to have an extra bathroom that is not listed in the county records.I plan to make some modifications, including removing a closet wall to expand a bathroom and taking out a kitchen island that contains electrical outlets and a switch.

She found a dead mouse in kitchen.

To convert the garage into an ADU, you would be adding a kitchen and bathroom.

Secondly the kitchen could use some cosmetic upgrades as well especially considering the bathrooms look so nice. 

Everyone who steps inside is wowed by the space and in awe of the 2-story wall of windows surrounding a 140+ foot redwood tree.