Additionally, I have one savings account for reserves for all my properties, which I add to every month. 

You may not be able to break the contract this year but would recommend getting additional estimates going forward if you feel it is expensive.

Additionally, the supply of homes for sale is constrained because of this and will be for some time putting upward pressure on prices in most markets.Thinking about renting your house in Seattle would be wise as someone else will pay the mortgage down, and rents and the value of the property will go up over time.

Her husband is also a GC who can help build additional units as needed if you get something that can fit an ADU.

I landed on the numbers I did because that makes it cash flow nicely for the buyer in addition to meeting my goals. 

I did just have my first GVR guest (arriving 1/14) ask me for one additional bath towel and face towel for each of the 3 guests.

The only exception is for on-site managers, like you'd find living in one unit of an apartment building and managing the building on behalf of the owner.

In addition, you'll have depreciation recapture at rates up to 25%.

Does anyone know a property manager that supports small self-storage rentals in addition to residential rentals?

The other site that I would be looking at is meetup.com as well, they have a lot of meetups in your area that you can attend to get in front of people doing the stuff you want to be doing.