A schematic set has floor plans, basic elevations and maybe an outline spec. It has few schedules, few details and no complete wall types.
A GC may ask subs for budget pricing at this stage. An electrical sub might price by floor area and by building type.
Treat any number from a schematic set as a budget. Write down each assumption. Name the set and its date in your pricing.
Expect the scope to change in design development and again in construction documents. Price each new set fresh.