How Much Can a Loan Cosigner Really Help Get You Approved?

[Burt L.]

I'm looking at purchasing an owner-occ SFR for myself for first time in decades and am no longer a W-2. Multi-family DSCR's were much easier to obtain, I'm recognizing.

I'm off from meeting the DTI ratio by a ways, although I've rented this same house for years and the debt service won't be too much over the rents. and I get a haircut on the rental property income, etc. I also can have early Soc Sec starting in a few months and receive a small pension. My 1120S income varies. I presume I would have to go FHA as they are supposed to be more lenient.

To use a related cosigner, do you "at least have to be close" or something along that thought-processs by the lender?  I would presume nobody would want one to be reliant on the co-signor. I've also read that the borrower has to "at least  have some income" but which is somewhat vague. 

What might be the general income gap a Cosigner will help a borrower overcome, or is it pretty broad-  as long as both incomes qualify together? Happy to say I don't  need a cosigner for the credit puposes. Thank you for any info.