I was on the Fusion site this morning. I am worried that I will not have the tools and knowledge needed to complete this project. I will probably call Fusion on Monday and ask a few questions.
I built a commander about 8 yrs ago. Sourced my parts from just about everywhere and made it work. It sure was cheap to build one then, no idea what prices have come up to now. As long as the parts are all spec assembly is not bad at all.
I've done it. First one came out great. Built it off a fusion frame and slide (not pre fit), Kart ez fit barrel and parts from all over. Gonna build another but got too many irons in the fire right now (2 M31s and a 10/22 magnum))
As far as specialty tools all I needed out of the normal stuff I had was a plunger tube staker, a sear jig, the sear/hammer test fit pins, the tool pack that came with the kart barrel. the rest was dremel, sand paper, lapping compound, calipers, and files/stones that were already in my toolbox. ohh and a 45acp finish reamer
As far as price mine ran about $1200 in parts. It shoots tighter groups and is no where near as finicky on ammo as my springer loaded ( and it only had problems with hornady xtp). ohh and no mim parts in it either.
I built 2 from rock island frames. I used parts kits from used guns that I bought off of gun broker. They both went together easily with only minor fitting. I built these for practice for when I get to build a nice one, however both are reliable and shoot good groups. I have about $300 in each one.