You're pretty much on target except the following.
Seller:
-Delingquent on property taxes and mortgage payment
-no equity
-lender about to foreclose
-just wants out
A seller doesn't have to be delinquent on taxes and mortgage payments to do sub2 deals.
There may be equity in the property
There may not be a foreclosure
Seller just wants out because they are out of state or they just want out due to divorce, death in family, health reasons, retirement, who knows..
Many tend to associate sub2 deals with desperate sellers and foreclosures but that's not always the case. Some people just don't like their spouses so they want out like NOW.