So, looking at my example you can easily see that a $2,000 build, which takes roughly $1,500 in materials, means the builder would only make $500 at best. Divide that by a standard 40 hour work week (which we all know something like this would take much more than 40 hours) and you're basically saying that the builder would make $12.50 an hour for his time.
Factor in the fixed overhead costs of being able to stand in a room surrounded by tools and call yourself a luthier and that $12.50 probably becomes negative very quickly!
A complete one-off custom has a lot of easy-to-gloss-over time and risk involved. Some things are obvious, like the difference between slapping a template down and buzzing out a body versus having to draw and make a new template for a new body. But it's not just that obvious time, it's also time to understand process changes, workflow changes, and other challenges of doing something different from what you've done before. It's about the entire mental flow of building something new. Building a bass is a process, it's not just stamping out a finished product based on a design. A plan or a design doesn't really do anything except give you references for shapes and dimensions. The process itself needs to be designed, too. You need to know the order of the steps, what fixtures or tools are needed at each step, and so on. And then besides the literal time involved, there's a risk factor in doing something unknown, which can mean either quality/functional impacts to the finished product and/or lost time in rework. If you quote a fixed price up front for a build, you have no way to recoup those costs. It's one thing to quote a fixed price on a reliable and known design, but quoting an unknown means you've got to guess at what that fudge factor is.
And that's a part of the difference between a "custom shop" order like your web configurated example above versus having an independent builder do it from scratch. Web configurators are meant to give the impression that you're designing a bespoke custom instrument but really you're just choosing from a menu of well proven and already established options. It's cheap to pay an overseas CNC operator to call up programs from a catalog versus paying a craftsman to build something from scratch. The end product may seem the same but it's two very different cost models.
All that said, I'm sure you could find hobby builders who would love to work with you on this project, maybe even well within your budget, mostly because they will do it for fun and don't care about the financials (or they don't understand the financials, or they have themselves fooled into thinking they're making money when they really aren't). Doing something for fun is really freeing! You don't have to pay yourself for the handful of hours you spend mulling over a new design while you're sitting at a desk in an office at your day job. You don't have to pay for shop overhead when you already owned the tools and the shop is a corner in your basement. And all that "extra" work and risk of rework that would cause a full time pro to lose their shirt becomes an enjoyable escape. Of course, working with a hobby builder means it may be a little harder to get a judge on quality/reputation, and there probably won't be a warranty or any sort of official means for recourse if the deal goes sour, and so on. All something to consider - you get what you pay for in this world.
But as stated, builder solicitation is not the intention of this forum. Which, honestly, speaking as a hobby builder who sometimes gets approached about building for other people, is kind of nice - it takes the "pressure" off and lets us all focus on talking about building, instead of having to think about putting on a pretty face and talking to or competing over potential customers.
If you want to find builders, there are a ton of highly active groups on facebook where solicitations are the norm. You can find them by searching facebook groups for phrases like "custom guitars" or "handmade guitars" or things like that. You can join, watch what people post for a few days, and message people who are doing things you're in to. And there are a lot of sellers on Reverb who mention in their postings that they are open to custom work. You can find them by searching terms like "custom bass." Might want to check those places if you don't find someone through the "indirect" approach Bruce mentioned above.
...or just forget all that and build it yourself.
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