The nice part about independent contractors is they usually are going to give you their best performance and their best advice. They usually aren't going to be held down by brand sales or salary comforts. This means you can trust their evaluations as purely honest and in your best interest. The drawback can be that if they are confronted with extra work, they are going to be tempted to find the quick and easy way out. Once the project is completed, if it works it works. As long as it passes inspection and what they said they would do, you can't fire them if it collapses after warranty. (Corporate businesses use this loophole too, btw.) When consulting with a contractor its most important to find someone who is honest and hard working. Slightly behind that is someone who has expertise. An honest contractor can always research what they don't know and tell you when they are in over their head. A dishonest or lazy contractor will sluff what they know they should do.
But let's assume you have two honest contractors, each working on a different part of the same job. It is essential that they communicate with one another throughout the planning and implementation stages. I once worked on installing a sound system for a church who was building a new facility. I pitched the system and all the specification requirements to the general contractor to be aware of. They accepted and ordered the parts. I scheduled myself to install at the appropriate later stages of construction. When I got there I had a few difficulties. First, the contractor and owners decided to move the system operations to the basement instead of the main hall. Let me tell you, that's a tough change to stomach on the fly. Especially when all the parts have been pre-ordered and I had a scheduled time install. If you ever even think that you might need to shift around system locations, let your contractors all know that ahead of time before the systems are planned. The issue here was that the general contractor didn't think it would be a big deal, so they went a head and built and wired for the change. Next, I had told the general contractor months in advance that the sound system wiring and conduit needed to be a certain gauge, of a certain insulation, and a certain distance from the rest of their electrical system. When I got there, I found thin wires run literally parallel to their electrical grid. The wire outputs were right next to the breakers. Next, when I got there, I was told the speakers we had ordered had been delivered but misplaced. I had to make do with a local store's cheap speakers tacked to the side walls instead of inset as designed. When I plugged in the microphones it was unsatisfactory because the electrical grid was interfering. So we had to pick up some ground loops. After that it was still scratchy, so I opened up the audio plug socket and found a mess of soldered wires.
Suffice it to say, the project was not ideal. We got it shaped up and sounding satisfactory to the owners. But to this day I'm not happy with the way it turned out. What's my point? It's not to vent. I kind of laugh about it. It makes the point that communication between multiple contractors matters. Each one of these issues were preventable if each party talked ahead of time and viewed the other as having expertise in their own field.
So if you have any project with multiple consultants or contractors: honesty, hard work, and communication are the top qualities to look for.
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