Because they don't actually send out a physical green card anymore,  it's all a matter of re-inspection and a PDF file being emailed, mailed or faxed.  

I provide clean, quality units updated to the market standard, and I claim income and expenses on my taxes.

You cannot file the 7 Day Notice to Quit in a court of law until the 12th, as you need to allow 7 full days and the 11th is the last of the 7 full days.If a tenant pays the rent during time frame of the Notice to Quit, then you must accept it. 

If you purchase a home that was previously a rental, they will have a file on it, and everything should be up to date with minimal repairs needed. 

I am trying to file the annual report.

It looks like the certification process may be a self-certification form filed with your taxes..Not too much red tape involved!

What would be the benefit to them over a standard offer?

https://www.biggerpockets.com/files/user/ChrisM93/... :)

The attached Affidavit of Immobilization was recorded and filed with the state, which makes the mobile home real property for insuring purposes.

@Kris Benson is correct. 7 square feet per person is considered the industry standard for market equilibrium, less than that, the market is considered under supplied (good), more than that, the market is considered over supplied (bad).