How much should you expect to pay, if anything, for an estimate, inspection or other kind of contractor consultation? The answer depends on the nature of your project and the policies of the companies from which you solicit bids.

But a few rules of thumb apply:

If you want to know how much it will cost to get something fixed, a free estimate is more likely. If you want a service provider to determine the source of a problem, you’ll probably have to pay for the diagnosis. For instance, if you know you’re missing roof shingles and want an estimated replacement cost, you probably won’t have to pay for a bid. But if you have no idea what’s causing a leak, you’ll need a roof inspection, which can cost $200 or more, depending on where you live.

Free estimates are more typical for smaller, uncomplicated jobs, such as window-washing. Larger, more elaborate projects — like a kitchen remodel — may require a consultation, which could carry a cost if more is involved than a remodeler talking to you by phone, visiting and then offering suggestions based on the visit. But if the consultation includes detailed design work, multiple plans and revisions, a contractor may ask you to pay for a full design, which can range from $150 to $1,000.

Because companies’ policies on estimates differ, be sure to ask questions. Find out what a quote entails, what form it will take, how soon you’ll receive it and if there will be any associated charges. Even if you’re told the actual bid is free, there could be a trip charge to cover fuel and vehicle expenses. Ask if a service provider might waive charges if he or she ends up with the job.

When getting estimates, seek as much written detail as possible, including:

* The basic scope of the project, including who’s responsible for each aspect of the work

* Start and completion dates

* Payment terms

* Cost of labor and materials

* Cost for permits to be pulled

* Proof of licensure, if necessary, as well as workers compensation, liability insurance and bonding

When evaluating bids, go through them item by item. Ask contractors any questions you have. When you make your final choice, be sure to read through and adjust any aspects of the contract before signing.

Don’t neglect to promptly update the unsuccessful bidders. It’s a simple courtesy, especially considering the time some spend compiling detailed estimates. A short handwritten letter, brief email or a quick phone call should suffice.

Angie Hicks is the founder of Angie’s List, www.angieslist.com, a resource for consumer reviews.