“Ugh.”
“Well, that’s money down the drain.”
“He’s been taken to the cleaners.”
“A fool and his money are soon parted.”
“He’s bought a pig in a poke.”
“He’s been fleeced like a sheep.”
“locked the barn after his horse was stolen.”
“bit off more than you could chew.”
“played ducks and drakes with your fortune.”
“Got caught flat-footed.”
“That’s as good as throwing it to the wind.”
“Dug your own grave on that one.”