Replacing a kitchen faucet: the basin wrench and the two things that go wrong

Shut both supply stops under the sink, open the faucet to drain. Disconnect the supply lines (a bucket under). The old faucet is held by a nut you cannot reach: that is what a basin wrench is for ($12, buy one). New faucet: deck gasket or a bead of plumber's putty, drop it in, tighten from below, connect new supply lines (always new ones, braided stainless), turn the stops on slowly and check for drips with a dry paper towel.

What goes wrong: the old supply stops are seized or weep when you touch them (replace with quarter-turn stops while you are there), and the new faucet's hoses are too short for your stops (a pair of 12" extensions, $8).