My clients and I have used Cost Segregation Authority with excellent results. 

I add people to my credit cards as authorized users for a fee.

So before you get ready to attempt to rip your Landlord a new one, first go take it up with the local taxing authority, then go have it out with the insurance industry, then gripe to the neighborhood HOA (if applicable), then maybe settle your disputes with Home Depot/Lowes and any and all trade contractors.

You may want to do some independent research on the respective Housing Authority website as well. 

You need to reach out to the housing authority, not the tenant.

Many taxing authorities are wise to this, and so require some form of disclosure on the sale price of the holding entity.  

Do buyers have the legal authority to give the tenants 30 days notice to move out immediately upon the deal closing if they don't want to continue having them as tenants?

Contact local authorities, consider long-term rentals (LTRs), work with a local realtor, and network with other investors to ensure the property fits your long-term goals.Good luck!

I am a software developer and I authored our current software, so interfacing to their API is not really a big issue, but I am not sure if anyone is familiar witth the process of using an API, If you arent familiar with the good ol nitty gritty programming, you arent going to get very far before pulling out all your hair.

It is a GREAT video on MTR with Jesse Vasquez (he has an episode here on BP) one of the leading MTR authorities.