After Paul shoots a ton of bullets into the head of the vampire pinned by the motel door, when the vampire is released and falls down revealing the wall behind his head, there are no signs of bullet holes or damage to the wall, just smeared blood. There would certainly be at least a few bullets lodged in the wall.
Although it is obvious in the film that vampires are extremely vulnerable to UV light, the hunters use firearms and knives only to fight them. Adding portable UV devices to their armory would make the job a lot easier.