Getting a mortgage hmmm?

Just wondering if when applying for a mortgage loan with bad credit but have people willing to co-sign for you and they own a house that is worth more than the house we would be buying is that pretty much a guarantee that we will be able to get a loan with them as co-signers? they tell me it is and that they want to do it for us. All I want to know is do you think we will be approved for something with them as co-signers with the whole house thing?