The simple answer is: “a lot”. Typically, more complex projects will result in a greater discrepancy in estimate prices. In other words – if you are getting 3 different estimates for a new granite counter top then the estimates should be within 15-25% of each other.
However, if you are getting 3 different bids on your bathroom remodel then the price spread will most likely be much greater. This is because the over-all scope of the job is greater for a full remodeling job, so there will be more variables in the job.
When you are comparing estimates, it is important to remember that an estimate is exactly that; an estimate or guess. The responsible contractor will ensure that the customer understands this when the estimate is given, and also when the contract is signed. Part of a contractor’s reputation is based on coming in on the budget stipulated in the estimate, so he will apply all of his experience to getting it as right as he can.
When writing the estimate, each contractor will make allowances for the factors that he can control as well as a few he cannot. There may be portions of the job that the primary contractor needs to subcontract. For example, if your bathroom remodeling job calls for the installation of an On Demand water heater, or a Jacuzzi Tub, there may be plumbing or electrical issues that are beyond the scope of his experience.
There is nothing wrong with calling in a subcontractor. Even if your primary contractor has the experience for the parts of the job which are outside of his expertise, he may not be licensed to do the work. However, calling in a sub further complicates the estimate, which in turn leads to differences in the bid.
Different contractors will specify different materials. Even if the customer calls for “the highest quality available”, this can be open to interpretation. One contractor may deliver better results installing prefabricated cabinetry, while another will specify less expensive raw materials but charge more for custom work.
The cost of doing business is another variable factor. You are probably aware that construction costs in the Pacific Northwest are generally higher than they are in the South or in the Mountain States. There will be some variance within the region as well. A South Sound Contractor may have a different estimate than a similar outfit from Everett, even though their results are the same.
Ultimately it is up to the homeowner to evaluate the estimates received. After evaluating the defined scope of the job, the quality of specified materials, and the contractor’s reputation for accurately coming in on budget, the best value can be determined. With the number of variables that go into the estimating process, it is understandable that the best value may not always be the lowest estimate.
You can find more information on why estimates vary in price by reading our “Why do the estimates vary in price” article.