Under writer issues

[Cam Jimmy]

I currently own (I have a mortgage on it) and live in my single family home. I would like to "house hack" into a multi family building. However I was asking questions to a couple lenders and all of them tell me that the under writer of the loan most likely will not approve the loan because I don't have a good enough reason to go from a single family to a multi-family unit. They keep saying " why on earth would you want to move to an apartment style unit when you are living in a single family home?". So I guess I am asking you guys... What would be a good enough reason to tell the lender so they would approve me? Trust me when I say that is the only reason, because my credit is excellent. I absolutely do not have the cash to put the 20-25% down, and that is why I must live in the multi-family. Any suggestions?