Trying to find a credit partner: Need Tips and Advice

A bit about the property

I have a property under contract for $405k. The property needs $35-$40k in rehab for an ARV of $550k. I am using a hard money loan for 95% of the purchase price and all the rehab costs. The hard money loan is at 10-12%, interest-only for 6 months. I have an expected rehab time of 3 months. The property will generate around $3300 gross per month with around $900-$1000 cash flow per month (before expenses). I plan to put away half of the money (around $450- $500) to cover any expenses per month.

I am looking for someone to cosign on my refinance. I found a bank that will do a 80% cash out refi, seasoning period of 6 months, and a debt to income ratio of 43%. I have around $4000 monthly income, and I am looking for someone with $4000 monthly (W-2) income and a 750 credit score. I want to take them on as a silent partner for 9-12 months till I refinance again (using 75% of the monthly rent to cover the entire mortgage expense). I am offering 25% of the gross rents (around $250 dollars) for the amount of time that they are on the loan. They will not put any money into the deal, and I will also be signing on the note (risk is split equally from a credit standpoint).

How do I approach and convince others to become a credit partner on this deal?

Would you take this deal? If no, why not? What would I need to do to make this deal better? 

Thank you in advance!