The conventional home buying wisdom is to buy as much house as you can afford. It is important, however, to limit your mortgage obligation to what you can comfortably manage, especially during times when the economy is uncertain.
If you are in danger of paying your mortgage late, send your payment via overnight mail. The cost of doing so is probably much less than your late payment. For example, a 5% late penalty on a $1,000 payment is $50. Sending the payment via Federal Express will cost you less than $15.