It's not a formal document, just a simple paper that spells it out and gives them comfort you won't be taking them to court later. 

Your use of the word "flip" implies that you are purchasing the properties primarily for resale and as such they are not eligible for 1031 exchanges.There is no statutory holding period or statutory laundry list for how you document your intent.  

The legal documents will chage state to state but the concept is what you need to explain.

They may ask for additional documentation.

Unofficial Notice Document of Foreclosure3.

There, you can find many different documents that you can download and even use, depending on the type of document and where you live.

Especially in a tenant eviction situation for  a service call make sure bring another person for a witness and also document everything with pictures, forms, etc.If it goes to court you need to have an iron clad case to bury the tenant in front of the judge with a credible witness, documents, pictures, etc.No legal advice given. 

cool thats good to hear, however the other side of the story thats not really talked about by lenders is that if you have a lot of other properties in the area you are trying to buy a property "in" then it may be very difficult to purchase an eleventh financed property as a primary residence unless it makes sense for your given scenario.Often times this requires:- a Great LOE - letter of explanation- supporting documentation like relocation letters from employers, LOE's from family members, spouses, marriage certificates, mammograms (show increased family size), etc etc list goes on- your  track record with other properties, like did you buy them as a primary then switch to investment properties (underwriters test to see your past "integrity," with mortgage transactions).

.), is it wise to already have a pre-qualified document expressing what you're allowed to purchase?

He sent me tax and insurance documents.