Subcontracting scheduling questions

[TotalNewbie]

I'm looking to sub-contract with a local vendor to do window tinting.

My question regards scheduling; A customer calls me and wants to schedule a window tinting. Do I tell the customer that I'll have to call them back(so i can see what my sub-contractor has available?)

I haven't talked these details over with my sub-contractor yet, but I'm just looking to hopefully bring some ammo to the conversation before-hand.

Thanks guys!