Self employment

maybe a bank statement? or a letter from the kuwaiti sponsor along with authorized signatory letter stating that your husband is part owner?

Basically the real question is, does he make more than 450 or not?

If he does, then you need to show (As mentioned by legacy):

Bank statements
Acknowledgement from the Kuwaiti sponsor that your husband is helping run the business and takes a share of the profits (or have a higher salary letter which matches with the bank statements).  I doubt that the sponsor would state ownership because legally speaking, doing it this way is illegal in any GCC country

If the sponser mentions ownership share would that be legal. Wouldnt that demand a registration

He does have the bank statements which has amount deposit from company where he provides services but they didnt accpept that. If we get a letter from sponser can u mention in detail what should we mention in a specific term. Thanks alot

How can the sponsor mention an ownership share if NONE of the legal documents can prove that?   in absence of any proof, the Embassy will not accept it.  It will be just a letter from a source that is not credible.

The only way as I mentioned before is that the sponsor needs to sign an agreement with you that allows you to a share of the profit and then the payments into your account should have relevant proof that it is in fact the share of the profit.