In Utah County the cheapest “House” for sale is 600 square feet, 2 bed, 1 bath, at $300k.
So at current interest rate it would be $1,800 a month mortgage(assuming you put the 60k down payment! A decent amount more if you do 3% down.)
The cheapest condo/town in utah valley is 205k, 1,100 square feet, on a 400 square foot lot. But due to a $500 HOA fee the monthly cost is still 1,700 a month (assuming 20% down).
With 3.5% down they’d both be closer to 2.1k +PIMI.
So yeah, how is where you live doing?
Out of curiosity I Googled the term “backhouse” and apparently it wasn’t that unusual around the early 1900’s. They still exist but most people are unaware because they are out of sight unless the front house gets torn down, even then it just looks like a house with a big front yard. Growing up in the burbs I never saw one. In the early 80’s lots of my friends rented them because it was cheap