Now, the new PM told me, that she will ask the tenants to copy the keys.

I was hoping someone here would have a template or copy of a letter/document that you send to tenants to let them know of the changes in ownership, and to notify them of our plans, expectations and and how to direct their rent payment to our accounts etc. 

Do they have a current lease, and if they do, do you have a copy of it?

We signed the paper at the end of the exit meeting but I don't remember the full content of the checklist and landlord didn't send me the copy yet.Landlord agreed that they will send us the security deposit back in few weeks along with the move out checklist.

Complete a W-7 form and provide a certified copy of the investors passport.Speaking from my personal experience, not giving advice... 

When they IM me I simply copy and paste my generic "Here is the link response" and after/if they fill it out then I decide whether or not I want to talk to them.

The ad copy is also important you need to give them a reason to sell or a reason to deal with you directly, an example would be "Tired of being a landlord?

Call them and have the conversation: How busy are they, recent jobs completed, ask for a copy of license and insurance and photos of past work, as well as professional recommendations (What other companies would recommend using them). 

If the previous PM has in writing that the previous owner was going to discount rent, ask for a copy and go back to the previous owner for the money.

I got my copy of the book a little while ago and gonna I'm be starting it soon.