I townhouse is slightly better than an condo. A condo is a glorified apartment. My distinction between a condo and a townhome is townhomes share walls. Condos share ceiling/floor.
I get my number a very simple way, average new (built after 1998) 2 BD apartments rent for $1500. At 7% interest, that’s a loan on $225K. The “owner” then picks up illiquidity, property tax, insurance and HOA dues.