When the younger Glick brother is abducted (and later presumably murdered by Barlow) he's wearing a jacket, t-shirt, dungarees and sneakers. After which, he appears to his brother wearing pajamas.
At 7:30, Bonnie tells Larry Crockett that her husband, Cully has to go to Portland for a pick up. She couldn't possibly know that because Straker doesn't have Crockett set up the trip for Cully until 27:20 in the movie. After which, Larry Crockett would have known about Cully going to Portland before Bonnie would have.
Why did Larry Crockett wait so late to go to Bonnie's house? According to Cully, the trip to Portland and back was supposed to take until midnight or after. Mike and Ned go all the way to Portland and drop off the crate at the Marsten house before Larry Crockett shows up at Bonnie's house.
At 1:30:00, when Mike starts to fill in Danny's grave, the sun is out and the sky is blue. The camera position changes and now, the sky is gray and there is fog over the town. The camera changes again, and it's back to sunny with a blue sky for the duration of the cemetery scenes.
When Ben and Bill are driving around town preparing to go to the Marsten House, then sun keeps changing from low to high, and back again.
At 2:13:00, Barlow comes crashing through the window into the Petrie's home. The fact is, a vampire has to be invited into someone's home. Jason substantiates that fact when he tells vampire Mike that he "revokes his invitation" so Mike wouldn't be able to come back. Therefore, Barlow should have never been able to enter the Petrie's home without an invitation.
Straker carries a bundle from his car into the cellar of the Marsten house, and unwraps it to reveal an unconscious Ralphie Glick. However, the bundle he carried in was much to small to contain a 10- or 11-year-old boy.
At 2:29:33, after seeing Mark open the bulkhead doors and go down into the basement, Susan runs to the basement entrance and briefly pauses. As she does, you can see that there is no outside wall to the house. The clapboard siding is only five boards high and you can see the trees and blue sky where a wall should have been.
At the beginning, when Ben is standing in the driveway and looking up at the house, Straker opens the front door and comes out. If you look closely in the crack of the door, you can see the sun coming through Venetian blinds. Later on, when they show the interior of the house, you can see that there are no windows visible on that side of the house.