A professional contractor should know their costs. If they give you a bid, this is based on their calculated costs and risk.
If you are comparing bids ‘apples to apples’ and some companies are significantly lower, you have to ask yourself, how can they can afford to be so much ‘cheaper’ doing the same work? There can be some legitimate reasons, like the scope of the work and certain assumptions, they somehow have lower overhead costs, or they have a special deal on materials. Most often, though, something is sacrificed.
When you are looking for high-quality, with longevity and attention to detail, expect to pay what that is worth.
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