Excellent question!
Marvin
No autopilot in those numbers?
This is one of many reasons you see numbers from a Vans estimate of 90 verses others stating 150,000, quite a range. Vans has no choice but to estimate a basic VFR machine and let the actual builder make the final decisions. For example, lets say we want an autopilot. Below is a range of autopilot options with just one supplier, Garmin.
The Garmin G3X Touch system has all the software built in. Lets say we want a wing leveler like an entry level IFR GA aircraft from the 80s and 90s. One GSA28 servo is $750 plus mountng kit, which is less than $100. We now have a fully functioning wing leveler, but course guidance is thrown in gratis.
Lets say we want both lateral and vertical Nav. Get two GSA28s for $1500 plus two mounting kits.
We want yaw damping? Simply unheard of in single engine aircraft a few years ago and only available in the top level singles today. Get three GSA28s for $2250 plus three mounting kits.
Wow that is a lot of capability, I bet we now want a dedicated autopilot controller head mounted on the panel rather than using the touch screen. Garmin will fix us up with two options the GMC 305 or the newer GMC 307 for $750 or $1099, respectively.
So autopilot is available at anywhere from $850 to $3650 from the same supplier. This is the basic decision tree we will follow with each and every step in the build process. It is both stressful and exhilarating at the same time.
Enjoy the journey.
Respectfully,
Marvin
P.S. - One last thought, I see many completed aircraft for sale at less than it would cost to build. Give it a few years and -14s will become available - a wing kit is already available on this very website. But, for some of us the build is as fun as the flying.