They don't. One includes it; the other leaves it to us. Pricing our share makes the gap between the offers much smaller

Make a shared scope table: who supplies each item, quoted cost, and any unknown allowance. Add your internal work, then compare totals for that same scope

The presentation mismatch is clearer, but the full estimate still has gaps. I can improve the comparison without calling either offer the winner

You've removed one source of mismatch, but the remaining gaps still limit what the comparison can establish