Keys?

I recently bought a 1997 ford fiesta which seemed fine at the time now ive got it home and the key seems to spin in the drivers door lock without engaging the lock it is possible to unlock the passenger door but this also takes some effort, im now having a similar problem with the ignition it doesnt always turn over at the first go, sometimes the key has to be removed and retried, why is this and would it be expensive to fix?