German phrase
Im Gegenzug müssten Sie ~.
Meaning
In return, you would have to ___
When to use it
It states a duty in return. The wording is polite and suits negotiations over costs or effort.
Example dialogue
Im Gegenzug müssten Sie die Kosten übernehmen.
In return, you would have to cover the costs.
Das müsste ich erst prüfen; wie hoch wären die Kosten ungefähr?
I would have to check that first; roughly how much would the costs be?