Continuity mistake: When Prue was talking with the shut-in and the security guard comes up and knocks on the door you can see the the chain is on the door. When he knocks again and says he is coming in and tries to open the door the chain is off.
Continuity mistake: When Prue is in the basement with the priest she has curly hair, but when she comes upstairs to vanquish Vinceres it is completely straight, but she definitely didn't have time to straighten it.