For my 3+ bedroom homes I house traveling or relocating families, work crews, and displaced families.

Consistent singles and doubles add up significantly over time.

Con: The rate on HELOC is more than double the first mortgage, and I worry about the rising rate.2.

Working on getting a new septic permit so we can add onto it, and increase the bedroom count to 4.

Working on getting a new septic permit so we can add onto it, and increase the bedroom count to 4.

. - if the city water pressure is low in your area you might need a fire pump which could double the cost of your sprinkler system.

(There are also fancy lofts for much more per bedroom.)I just heard from someone who is looking at my furnished listing that they'd like to pay $950/bedroom and think that's justified based on the other places they're seeing.

I did this exact thing last time a tenant asked to install a TV mount on the wall of a bedroom.

Bedrooms are carpet. 

You'll likely see variation (even within a zip code) based on condition even though all might be 3 bedroom 1 bath homes (as an example).