I have a coupe of kits that I bought in the days when they were still reasonable. I have the parts, but I don't have the tools. Considering that I am unlikely to build another kit ever again (I just saw a $449 AK kit the other day), it really does not make a whole lot of sense for me to buy the equipment. I wouldn't be averse to renting, though.
So, for the AK I need the riveting tools and for the FAL I need whatever gizmo is used to time the barrel. I don't really know if I need to have an action wrench or can get by with a vise and aluminum jaw liners. I suppose whoever has a tool for this would know. I would also need headspace gauges to figure out what size locking shoulder I would need.