I've built 6 kits myself and helped friends and family with another six or so. Mostly imbel kits on DSA or imbel receivers and a couple of StG kits. I just purchased the Sarco Argentine kit and plan to build it on a Coonan receiver.
I have all the tools I've needed so far. But there's always the chance of encountering unexpected problems. .. An excuse to buy more tools is always welcome!
Here's what I had in mind for the build party schedule:
1st meeting (social meeting): everyone who has a FAL brings it for show and tell, discussions of what kits are available, discuss different FAL variations, discuss different receiver options, discuss compliance parts options, and maybe watch some of "Gun Plumbers" video
2nd meeting (shop or garage meeting): once everyone has their kits in hand; how to properly inventory, evaluate, and clean the kits, determine and order furniture, compliance parts, receiver type, order barrels, etc.
3rd meeting (shop meeting): once everone has their recievers and compliance parts; time the barrel to the receiver and establish headspace, assemble rifle, order proper locking shoulder, discuss refinishing options, furniture, optics, etc
4th meeting (shop meeting): once everyone has the proper locking shoulder; install locking shoulder, verify headspace, refinish paint or whatever
5th meeting (range meeting): test fire, adjust gas, and sight in rifle
These are the steps I've gone through myself and with friends and family. You could build the rifle in an afternoon if you plan well but it usually works out better if you build in stages giving time to understand what you want and ordering parts etc.