I know pilots who have found jobs with less than 500 hours, and they were jet jobs at that.
It does happen.
As for paying back the loan; this is something that the bank manager will have discussed before lending the money and contingency plans will be in place.
A positive attitude is a must when taking on a project such as self-sponsoring for a CPL. Also, it is often a case of who you know as well as what you know.
VFE, bank loan self-sponsorer!