As the budget announced, there's a program cap of $1.25 billion over the three-year program. Beyond that, terms and conditions will provide more information about the program risks and how they're being managed.
The program parameters announced in the budget are one example of how they limit the risk to CMHC and the taxpayer. For example, the borrower would still need to qualify under mortgage rules for the insured mortgage in order to be eligible for the program.