Leveraging partners money and credit

[Vidal LeClaire]

my name is Vidal I currently have partner who ezcelent credit, great history with her bank, only problems is she has a mortgage on her condo. The bank says her debt to income will be too high and won't give her anymore money for any deals we find. Currently we are looking for 4plexes and up. I would like sum insight on sum strategies to leverage her credit and money (access to about 25-30K in credit cards) to pay for a down payment on a 4plex or better. I was thinking of telling the seller we have 20K to put down, and keep the rents until the rest of the down payment is paid off and we do seller financing from there. Is this a good idea? Or are the better ones to use?