Seeking advice on first rental with existing tenants

[Rick Reed]

I'm trying to decide how best to approach an offer on my first rental purchase. The seller's agent states that the existing tenant would like to stay on a month to month basis, but has no application from them, they have a small dog (the place wreaks of urine), no security deposit, the owner is the manager without any maintenance records, and the rent is a good $200 month below market. The place needs a lot of basic work too just to make it rentable and meet basic code requirements. I haven't gotten an inspection yet because I'm still trying to figure out how to negotiate the deal, so who knows what other issues need to be addressed.

Is it possible to word a contract to specify that the tenant must vacate before closing? Do I just make an offer, close, then give notice to the tenant that they must leave after 30 days? I would prefer the tenant leaves prior to my inspection in case they do any damage because they were asked to leave.

How would you address this issue?