It might be weird but I would like to point out:
What means to be "building your own saber" ??
Surely it does not mean by smite your metal out of mineral ore and creat your battery pack by hand and....
Yes, I would like to point out that maybe the "shells" of sabers are pre-made, or at least, a bunch of ready mde parts are available for the more "common" and non complicated parts. You maybe there is already a huge collection of hilt parts, grips, on/off/reset buttons, streamers and what not for building sabers, along with a bunch of different pre-made tit-bits for the construction work.
So obviously there would be sabers with similar hilts, maybe they just happens to be built from Hilt style B-A01, with Ziggy Series grip, Tamiya switches and Wave on/off lights. Just the same combination from the more available parts really. Not everyone would use a Rancor tooth as the "start button" of your weapon.
Maybe this sounds funny, but as we know it there is quite some daman for sabers, training or not. And we do know sabers do subject to wear and tear. So it would be reasonable for jedis to mass produce the common parts in some way, and you don't need to be force sensitive to build things like wires and grips.
Sure the delicate parts like the crystal calibration would be left to individual jedis, but those would not affect the look of the saber too much, as we know it most sabers would be blue or green... or yellow for faded ones, due to crystals. And I won't be surprised that jedis would forbid the use of red sabers, and discourage colorful ones.
"oh master, if shaft can have a purple pimpstick with BMF on it why can't I have the pink one with the Gucci grip and purple streamers and that extra lipstick dispenser?"