I have a lot more research todo my self and a lot of phone calls to make, and I'm interested to see the responses here.

Here are some of the strategies I've seen marketers use to make their efforts less effective:1: Ask me to call as soon as possible, but don't include a phone number anywhere on the mailing.2: Don't include any sort of contact info -- company name, address, etc. -- so that I have no way to check to see whether this is a scam. 3: Send me offers to buy for cash properties I have never had any sort of interest in, ownership or otherwise. 

Please give me a call anytime at [Contact Phone].

@Michael Ash in addition to calling the police, you could ask them to back it up with photos or video, everyone has a smart phone these days so that shouldn't be to hard, assuming it is really happening.Could just be they have a large, close family that likes to visit, there is certainly no crime against that.

They need to want to help you and return your phone calls promptly.In the begining especially, alwaye do a math analysis and try to look at your prospective properties before you make an offer on it or at least have a clause in the sales agreement that allows you the time upfront (about 10 to 15 days)  to make a detailed inspection and possibly back out of the deal without a penalty that will hurt you too much.  

Managing managers takes wayyy less time than managing properties, and there's never been an issue I couldn't fix over the phone from long-distance.

I use rentalutions for my properties.I have 7 properties, 25 apts and about 50 tenants.There are a lot of roommates.I definitely recommend it as it really makes rent collections easy.Their responses are generally good and helpful, mostly via email rather than phone calls.They have a reports section which comes in useful for lease renewal reports, late payment reports, etc.I do use it to syndicate rental listings, but they don't seem to post onto Craigslist, which is where I get a lot of responses.They do have Zillow, Trulia, streeteasy, etc.

The phone is already paid for.Hmm.

I know there names and a PO box but I don't have a direct phone number (other then office of manager on site).

Is it my best interest to phone back or wait until the notice has been posted.