The tenant was suppose to be out by the close of sale. They were given multiple notices by their landlord and did not move. I took possession of the property and want them out. Can I just proceed with a 3 day notice to pay or quit? I want to proceed with a unlawful detainer but not sure what can be done.

Find out the terms of any pre-existing lease... if they are month to month, then you can serve them notice (make sure its properly served) their month to month is not being renewed and that they have to leave. That is 30 days in most states. If they aren't out by then file for eviction.

If they have a lease that is not yet expired then its not as simple and you either have to honor the remainder of the lease or offer them financial incentives to leave earlier.

You should not have closed with them there, you are now a new owner and have to start from scratch.

1. if they have a lease you are now obligated to honor it

2. if on a month to month rental, you can accept this months payment but give then notice that they are to move. If they have a written rental contract you will also have to honor it, on the terms of giving notice.

If they do not pay you this months rent, then you can give them a pay or quit notice. But they have to be given a chance to pay you.

Also the trouble with pay or quit, if they pay you, then you will have to start from the beginning on a normal eviction anyway