The current window is very tiny and we received an estimate of around $3k to update.

PS: I tried to build a tiny village in Memphis but zoning requirements prohibited building.

I will have very few expenses (especially with the paid off house or tiny mortgage) and have a few income streams the properties being the biggest.

But rentals can also be very high (capitol hill tiny one bedrooms in old buildings are 2,000 a month easy). 

Love the tiny home movement !

. $400Purchased at Sears OutletWhirlpool stainless dishwasher (new, tiny hidden dent) -- $275 vs. $500 Purchased at discount builder supply stores (Habitat for Humanity REstore, Seconds and Surplus, ShoptheBoss.com) All this stuff was brand new in the box. 4 brushed-nickel ceiling fans/lights -- $160 vs. $400ish2 brushed-nickel vanity lights -- $40 vs. $100ish4 24"x96" granite slabs -- $400 vs. $1,500ishUndermount sink $150 vs. $250ish660 sq. feet of handscraped engineered floating wood floor -- $660 vs. $2,000+40 sq. feet of glass mosaic backsplash -- $40 vs. $320ishCeramic tile for master bath -- free (I used some the people who sold us our house had left in the garage) vs. $200ish1,000 sq ft of FHA-compliant carpet installed with pad -- $1,100 vs. $2,000ish

Pending local regulations and zoning restrictions, sounds ideal for a tiny house community. 

Not to hijack the thread, but I see you're in Eastern WA so I'd love to hear your thoughts on an idea I've got for a place in Leavenworth... https://www.biggerpockets.com/forums/530/topics/472419-should-i-build-a-tiny-cabin-as-a-str

Or a tiny home.

I would love to put tiny homes or container homes on the mobile home lots and then do short term rentals or maybe even vacation rentals.