If so, at the confirmation hearing there should've been a date set for when the previous homeowner should move out by

For example, for each buyer client you have, call homeowners in their target areas and let them know you have qualified buyers searching in the area.

If you really want to get a deal from tax liens, contact the homeowner just before they reach the 5 year deadline.....

You'll need to market to homeowners for months/years before they decide they want to sell their property.

But also, you'd get a better rate just buying your home with a home owner loan. 

Once the homeowner is gone, the room renters usually leave the house a mess and leave things behind once they leave.  

The maximum occupancy permitted in a vacation rental unit is two (2) persons per bedroom larger than 100 square feet, plus one (1) person per bedroom greater than 70 square feet but less than 100 square feet, plus two (2) additional persons, or a total of eight (8) occupants, whichever is less.The homeowner must post the required information on the property.

If the homeowner has a material change in circumstances (transfer of title to his house) then he needs to inform his lender.

I saw a local FB group post early this year from someone asking how to evict the homeowner from a home where the investor bought the lien a few months before.

I feel like a lot of these "cash" transactions are a product of homeowners sitting on record equity.