Low estimates typically reflect one or more of: undisclosed scope exclusions (the low bidder has excluded items the higher bidders included — watch for these in the change orders after work begins); lower specification quality (cheaper materials, less experienced labor, inadequate subcontractors priced); inadequate labor hours (the estimate assumes faster production than the work requires, and the overage will appear in the final billing); or deliberate low-balling (pricing below cost to win the contract with the intention of recovering margin through aggressive change order pricing once the client is committed). When comparing estimates, ask each contractor to identify the specific items that account for the difference. If they can’t, the lower number is not a better price — it is an incomplete scope.