How do you get the owner out of the home you have purchased from a trustee sale?
Best bet is always to negotiate cash-4-keys with them. If that doesn’t work then proceed with eviction.
Typical cash-4-keys deals is to give them roughly one months rent in cash if they move and leave the place clean in 2 weeks. You might have to enrich that to 2 months rent so they can afford to move and pay first + security deposit.