Pricing kits? Those are CHEAP. Lol. If you did the research on what full custom loops are, are for, how they work, why they work, the work expected and the parts to accomplish the work, you'd realize that a decent loop will cost upwards of $700 easily. $10 a fitting avg, 2 fittings per component minimum, some loops can use as much as 20ish fittings, rads run $50-$150, pumps run close to $100 each, distro plates are $200ish or more, cpu blocks are $100ish, gpu can be far higher.
The only cheap item in the entire loop is the distilled water.
Kits... 😂
Those are the toys you get in a Happy Meal, just saying.