What do I need to know and look for in the kit?  What can I expect to pay for a receiver and a FAL builder to put it together?  I recently traded off my 50.00 and got the itch again

It seems as though you may financially be better off to buy one that is already assembled.  The kits run $700-$800 pretty regularly, while it is often a struggle to sell a completed rifle for $1200-$1300.

Kit= $700 to $800, receiver about $400 including FFL transfer, US parts about $100, at this point you are already at the upper end of what a complete one sells for.  Then you have to figure the cost of the build if you don't do it yourself.  I am not sure what smiths charge for that, but it is bound to be $250 or more.

+1....

I loved building everyone of my FALs, but like already stated, may  be cheaper to buy one already done.