bought the car and the driver side rear lock didnt work. today, the front passenger power lock stopped working. only the driver and the right passenger rear work. what could this be?? the locks that are broken have to be pulled up by hand and will not work with the switch on the door.

 

Most likely the power lock actuators. You have power because two work. Door panels have to be pulled to access parts. Usually the actuators sell for $70 or so. 30 to 45 minutes per door. $140 in parts + $120 in labour taxes etc... $300 or so.