Newly acquired property - tenant with no lease - want them out

[Luke W.]

I made a rookie mistake last week. I got too excited to acquire a new rental. The seller had a man living in the house that was doing work on it (it was actually quite good), but he had been staying there for a year or so for free while doing so. I bought the property with the intention of finishing off the work and renting it out. Unfortunately, I just took the seller's word for it that the tenant had vacated at the time of closing. I know I should have confirmed and waited to close until he was actually gone. Now the tenant and seller will not return my attempts to contact them. Of course. However, it is what it is at this point. My question is this. I want him gone, and he isn't on a lease, how do I go about getting him out? Do I serve a 5 day notice and try for an eviction, or am I required to give a 30 day notice?

PS- I will be calling an attorney tomorrow, just thought I might grab some ideas tonight if possible.

Oklahoma City, Oklahoma