Typically, mortgage brokers ask for a Notice of Assessment to prove income, I don't think they'd use it to confirm funds for a down payment. I'm not all that familiar with the FHSA, but it seems like an extension on what we have with the HBP, which lets first time home buyers borrow against RRSPs (retirement saving) for a down payment. In both of these cases, they are savings accounts you open with a financial institution. For the HBP, you need to prove these funds with bank statements, and I would think the same thing would go for the FHSA.