If it wasn't a rental, the owner might have been a moron who didn't file for the exemption and paid extra in taxes every year.

It's an extra expense to install and an extra opportunity for future problems with very little benefit to you.

Rent your extra rooms out using short term rental like AirBnB.

Our cash reserves can cover the extra expenses of putting in power and water lines(I own an excavator) and crushed concrete for the driveway amendment.

If you have a LLC and you want the extra coverage, each LLC will need its own umbrella policy. 

The Tellus app interface is really cool and I like that it has a lot of extra features (like move in and move out reports you can share with tenants with photos in the app).

Looking for advice in regards to planning, design, financing (Boston offers loans you do not need to pay back unless you sell the property - if you qualify), construction etc.If you have been through the process and successfully converted extra space into an ADU I would love to chat.

An extra wire provides a backup rough in in case an extra circuit is required in the future, or a 240 v is needed down the road. 

A co-op or condo will have HOAs and extra fees.  

For example, an extra egress or a sprinkler system.