Traditionally, banks required so-called "down payments" of 20% of the purchase price of the house (i.e. they were willing to finance up to 80% of the purchase price of the house, no more). At the height of the bubble, it was not uncommon to get mortgages with "no money down", i.e. with no down-payment (and 100% -- or more! -- of the purchase price of the house lent by the bank).<p>These days norms are in a bit of flux: many banks will accept a nominal down payment (at, say, 5% of price) and charge an extra fee for private mortgage insurance (PMI) until your equity in the property exceeds 20% of the purchase price (that will take a number of years, typically, if you pay mortgages on the agreed-upon schedules). This insurance protects the bank in the event of your default.<p>This is all negotiable (though some banks are more willing to negotiate than others).