I've witnessed probably hundreds of forclosures and landlord hearings and never put to much thought into it.

I could help you get signed up wit a Keller Williams Broker in MA which is where I work.

What you seem to want is some 5 step program to do a deal, you can wait for some nit wit to post that may tell you something you'd like to hear, but there is no such thing, sorry.So, you want to do brain surgery and you want some surgeon to give you pointers in a forum of what to avoid.

I've been thru this before in another state and 2 witnesses weren't required.  

While I have no doubt that cash-buyers receive a discount to some degree (in fact- I witness it everyday and regularly represent clients who are beneficiaries of this) I think that the extent to which it's reflected by this study is a bit overstated due to a hidden variable:A lot of cash purchases are made for value-add deals, or other cases where the property might face obstacles to financing.

@Gaylin W. it seems like you're going on tidbits of info and google- I would honestly go to a tax professional this year. 

This protects the company by giving them the ability to check with witnesses, gather info, etc. to defend the suit if it comes.

If that were the case, every Jehovah's Witness or vacuum cleaner salesperson would be arrested.

Do I need to take a witness or something?

You, or your agent, should then review the estoppels with the respective tenants; record any missing information or variation to the information presented {this is how you find side deals or catch un-ethical vendors}; and have the tenants attest the estoppel (i.e. sign with a witness).If the attested estoppels differ from the information provided by the Vendor, you go back to Vendor to work why.