A low overhead line may not mean a lower bid

When comparing custom-home bids, how do you tell whether a lower overhead and profit line reflects a genuinely lower total cost or costs folded into trade and material prices? I’d want to compare the same scope, but I’m not sure how consistently builders present these amounts.

What’s reasonable to ask each builder to clarify about general conditions, including whether supervision, temporary utilities, and site security are included? I’d also like to understand how the fee is calculated when allowances change or a change order adds work. Are there particular definitions or bid details that make these comparisons more reliable?