PLOT BABY: garage sale antique

At a garage sale, MC1 buys an antique [urn?] which they think will look nice on their mantle. When they get home, they realize its full of ashes....

This could go a ton of different ways... the spirit could start haunting them in a harmless way, making it a comedy..... or they could become more sinister, creating a horror story..... or it could be a mystery and it could spawn a ghost who needs to have their murder solved before they "cross over"....