Boxabl vs Addition To Detached Garage for ADU

[Greg Kitzmiller]

I have a property with a detached garage that's partially converted that I want to convert to a living space. I've talked with architects and contractors and have gotten either a lot of friction or >100k estimates to add a bathroom/kitchenette to a detached garage. 

Boxabl for $50k seems like a simple way to cut through the labyrinth that an addition seems right now. 

I live in Portland. Is the above a good assessment or am I just not finding the right people?

if I'm on the right track are there any good alternatives to boxabl?

[Roarke Van Brunt]

Contractor in Portland here. Prices on everything is pretty crazy right now, but 100k+ seems expensive.

I can imagine how you could get there but it would probably be utility driven (Water, Sewer, power). I doubt boxabl has that included for that 50k. 

With permitting watch out for the SDC's (Systems development charges) from the city for the extra fixture counts. Almost all the jurisdictions in the area have online forms to help estimate permitting costs. They add up fast. A few extra sinks, and a toilet can get pricey in most of the local jurisdictions.

Do you have to do a lot of underground work for the sewer and water? Is another panel, or worse an upsize to your electrical service needed?

This is from the boxabl FAQ on their website and is probably where your missing $50k is.

How much will it cost to setup a Boxabl?
The Boxabl Casita is fast and easy to setup. For $50,000 you get a house. Whats not included in that price is your land and site setup. This can include utility hookups, foundation, landscaping, permits, and more. Depending on your location and the complexity of your site, this cost can range anywhere from $5,000 to $50,000.