If you’re going to be working with a contractor, good communication between you is crucial every step of the way. Here are a few tips to keep in mind as you begin planning your project so you can keep the lines of communication open, avoid surprises and stay involved from the start.

It is critical. Too many people sign up with a contractor to have a particular job done, but they realize that they want something else in the middle of the job. Maybe they wanted to expand a living room, for example, but later decided they’d instead devote some of the new space to an expanded kitchen. That’s a big deal and can wreak havoc in a contractor’s plans, perhaps causing him to have to undo some of what he’s done or to spend more time than he’d budgeted on your home. It can also end up costing you a lot more than it would have if you’d been more sure of what you wanted at the outset.

Have you been watching a lot of HGTV? If you’re a devotee of the many home-improvement television programs out there, don’t let them lead you to believe that projects can be completed in half an hour — or even a day. Remember that the craftspeople often have plenty of assistants working with and for them, behind the scenes on these programs. Simply installing a door or sink can take much of a day if a few unexpected developments aren’t unusual.

It’s easy to forget that the world doesn’t revolve around us, but trust me, when it comes to home repairs and renovations, you’re probably not the only client in your contractor’s life. Some contractors may work only for one client at a time, but many will be juggling a few while they work for you. Part of the reason for this is that they may have promised to start work somewhere at a particular time, while work at another site has dragged on a bit longer than initially expected.

Sometimes clients like to hang around contractors while work is done, helping out. It can be a Good Thing or a Bad Thing. First, find out precisely what kind of help is and isn’t welcome from the contractor. For example, if a floor is torn up, you might offer your brute strength to tear up some tiles. But think twice before attempting to install Sheetrock or change an outlet. A little knowledge can be a dangerous thing, and if you do certain things on your initiative, you may end up causing damage or generating more work for the contractor who may have to undo what you did.

Contractors often scratch their heads when they encounter clients who are surprised that working on a house can be messy. (“How come there’s so much dust?”) If you’re going to have work done on your home, take some time to find out from your contractor what you can expect, mess-wise, and how you should prepare the work areas. You’ll save yourself from some unpleasant surprises, and you can minimize the pain, too. For example, if a wall is going to be torn down, you can prepare by removing as many objects in the room as possible and covering as many things in that room and nearby rooms as you can. (Clouds of dust don’t know to stop at thresholds.)

Many of us are used to thinking negatively about contractors, having heard horror stories about inept ones or, worse, scam artists.

Still, remember that bad experiences are typically shared more often than good ones. So while there are certainly more than a few dastardly contractors out there preying on unsuspecting homeowners, there are also many skilled and honest ones.