"We got the itinerary and arrangements set up but we're missing one more thing. Someone has to look after the house for us while we're gone." Lydia looked at Delia like she's crazy... crazy is more of an understatement eccentric, yes but crazy there's a fine line between the two.

They have the Maitlands that literally haunt their house. "But what about the Maitlands?"
"They're already dead and it's not like they'll have a problem with it."
"They did have a problem with us moving in the first time so I don't think they'll take to having a house...

Ding dong

Charles opens the door to see a young sandy blond pigtailed Girl Scout. "Hi, my name is Skye and I'm here support the Girl Scouts by selling cookies $4 a box." Lydia spots her and remembers meeting her when she and Beetlejuice turned their house into a haunted home and gave her a big scare. She also has Arrythmia meaning she's got a defective heart. "Skye, how would you like to earn a house-sitting, badge?" The young scout thinks it over and then looks to her sash with badges.
"We'll pay you and you can give the money to your troop as a donation." Charles told Skye who eagerly accepted the offer.

Now that they have a house-sitter it's just a matter of telling Barbara and Adam about it and hope they won't be too upset with the idea of having the young weak-hearted girl look after the house while they are away.