Be very careful about considering a mortgage or loan that would require two incomes in the first place in the sense that you can see how unstable our income is. The stress of needing one more child to pay the mortgage bill would be more than most can handle. Better to live within one income for essentials and the daycare income as a supplement as much as possible. I know not everyone can do that but be wary of considering what you make now as your family income and going into debt with it because in a heartbeat part of that money will be gone and you will have no way to pay the loans back.

When we got our mortgage they took my husband's income and half my income (the taxable part) for the previous year into consideration - using the idea I could be only half full at any given time.

It is getting harder to get a loan on self-employed income. My daughter applied for a line of credit just to have a safety net should an expense such as car repairs come up and it was quite the messed up process to get approved. Yes 2-3 years of tax receipts, payment history, length of time with the bank etc were all considered.