there are buses but since it is latin america, i wouldn't assume that they run on a reliable schedule. if you are going to stay anywhere other than the resorts actually in Cabo San Lucas, i would recommend an all inclusive or a resort that has shuttle service to Cabo and/or San Jose or else you'll be stranded and have to use the bus or take taxis to get anywhere else. if you don't plan to leave the resort that you can probably get by without a car.