Do you need proof of employment for the METV if you're retired and only work on short projects?

Question..for the METV you NEED proof of employment? I work on and off, never more than a couple of months..not because I have to, but because I want to. Basically I sold my assets and retired very early, so money is not an issue, and I only work when I see a small, short project that interests me.

I understand that it might be hard for me to get the METV since I am neither a business owner nor am I employed. Is this correct?