If the server can be trusted to interpolate on a market schedule in many cases, ask the clients both questions at once.

"How many bananas do YOU have NOW, and while you're at it, what's your schedule of pricing assuming a market supply of X, Y, or Z bananas? If it's not a simple interpolatable schedule, i.e., if you use complicated models when the market isn't exactly X Y or Z, let me know that too and I'll have get back to you."

If it's nearly always a complicated model or the affine schedule is really huge, then this approach is less valuable.