Continuity mistake: In 'Tabula Rasa' when the loan shark's henchmen throw a stake at Spike at the start it flies over his head and hits a tree. But, if you compare the angle they approach from with the relative positions of Spike and the tree you can see it would have had to do a 90 degree turn in mid air to fly over his head before hitting the tree.
Continuity mistake: In the beginning of the show, Buffy has two necklaces on, one long and one short. However, when Buffy, as Joan, is telling everyone her plan to get away from the vampires, she only has the short necklace on. Then when she is outside, running from Spike, as Randy, both necklaces are back on.
Continuity mistake: When Buffy and Spike (as Joan and Randy) are fighting Bro'os vampires, Buffy kicks down a post box to stake one of them. The pole supporting the post box breaks away at a jagged angle. But when she uses it to stake one of the vampires the end that she uses has suddenly changed to the traditional triangular point, only to return to its original jagged angle immediately afterwards. The shot of her staking the vampire is not a side angle of some uneven ends. Watch as she backs away from the vampire after he's been staked, it is a fully triangular point.