New landlord and need Eviction HELP!!

[Allen McGlashing]

Hey guys so I have just bought a 3 unit house with 2 apartments already rented. I spent most of the day over there fixing things and cleaning and I meet the tenants again and started talking and one tenant gave me a little gut feeling like he will become a problem as he's telling me about his financial situation ( which isn't to good) now the first of the month is Monday and if he doesn't pay the FULL amount in rent I want to get the ball rolling on eviction by starting out giving a notice saying no rent was received then a notice to quite. Something else struck me when I was leaving another person came out of "HIs" apartment which the seller had asked me a month ago about his friend falling on hard times moving in and I said "NO" I want to do it my way run an application. So basically I assume he is living there now so that will give me another way to help in the eviction. The lease gives 15 days of another person living. Any tips on how to prove he's living there, no extra bed or anything.Just need some help this is my first property and I'm a brand new landlord that depends on the other two units rent to get me by.