When you mark up materials, you need to consider how much liability you are looking to assume.
Do you intend to simply sell and deliver the fixtures separate from installation, or do you intend to warranty the fixtures as part of a complete package with the installation?
Imagine if a fixture goes bad, and has nothing to do with the installation. Will your fixture warranty include all labor associated with changing it, or will your warranty only cover the fixture itself and charge for labor to uninstall and reinstall?
If you offer a no hassle, no questions asked warranty, thenyour markup has to be higher. Also take into consideration how easy or difficult it might be for you to get it replaced.
Also, do you share markup details with the customer? In other words, do they see their light fixture on the internet for $350 ? And you're asking for $700 ? That can be hard to pull off if they know how much you're spending.
Basically there are two rules of thumb:
First, perception is everything. If they think you plan on marking up 60% just to order and deliver, they probably won't see how it's beneficial for them. But if you bear 100% of the warranty responsibility, they may not have a problem paying a 100% markup
Second is this ----?extract as many funds as possible. Part of thus is in the perception. High end customers have money, and they didn't get it by being gullible.
The more service they perceive, the more funds you can extract. Value is a relative idea.