The engine is knocking very loudly, the van runs hot, leaking oil, radiator is leaking, oil leaking everywhere
My car has 212000 miles.
My car has an automatic transmission.
From what you’ve described, I have a feeling that you may need a lot more work done than your quote of $920 to fix this vehicle. Be aware that an engine knock can be an internal engine problem requiring an engine replacement or overhaul due to bad crankshaft bearings. You overheated the engine and this may have damaged the engine heads and head gaskets.
I would recommend having a second opinion done one your vehicle before any money is spent to replace the radiator or other repairs. Consider YourMechanic, as one of our mobile technicians can provide you with a diagnosis of the engine knock and oil leaks. Best of luck.