I'm not sure any of our family's cars would get us very much as a part-exchange.
Maybe a spoke key... Not a very posh one.
I'm reminded of the (pre-Velvet Revolution) car joke:
Bloke walks into
Halfords.
"Can I help you sir?"
"Yes. Fuel cap for a Skoda?"
"Sounds like a fair swap to me, sir".
There are more where that came from, but I wanted to stay on topic.