I can buy you once but I can sell you twice
You buy something once and then sell it twice so bad that it’s like it never existed. It means you’re the worst kind of cheapskate and the item is totally ruined.
He bought that watch for $200 and sold it for $10 and then sold it for $2. He’s a total cheapskate.
She bought that dress for $100 and sold it for $5 and then sold it for $1. She’s a total loser.
He bought that bike for $150 and sold it for $10 and then sold it for $2. He’s the worst.