However, through research of other markets, I've noticed the higher cap rates in other cities that align with my goal to increase my passive income w/possible appreciation.  

A 'pay or quit' or 'pay or vacate' is a 3-7 day (depending on your state law) notice to the tenants to pay the amount owed or vacate.  

The seller says he will give notice to the tenants as soon as we go through legal review and I put down my earnest deposit, but it's no guarantee the tenants will be out by the time I close.  

. - Perhaps you're right, but I would bet that pushing the heating costs on the tenants will result in a rent decrease that is less than the fuel savings; so you will get a net-positive gain. 

I saw ($1229) when I clicked on 'notice of proposed taxes' but that could be based on a previous OO.

(you decide this figure...I usually ask for 4x) times the stated rent and show no negative credit reports and co-signer must be US Citizen or legal resident.Will you deny rental if any of these are on the applicants credit/rental history:---past due rent or an outstanding balance ---prior/current landlord gives a negative reference or refuses to give a reference ---Three (3) or more 72-hour notices within a period of one year ---Three (3) or more NSF checks within a period of one year.

I am looking at a property that has Notice of Trustee Sale tag and wondering if I can still contact the Borrower and make an offer before the sale. the sale date is still almost two month away so wondering what my first step should be.

Wholesaling is already low yield strategy so the goal is to decrease the time, money, and effort put into each deal.Go back to your buyers and get all this information FIRST before you do any more shopping for potential deals, so you can avoid wasting any more marketing dollars (and time and effort) on potential deals that will never get bought.

And if he does not clean up, give him a 30 notice to vacate.

A 3-day notice to pay or quit was sent out on the 6th, and still nothing.