12" Channel-locks and a pair of 10" too.
Locknut Pliers - good for 1 1/2" and 1 1/4" waste tubing.
Faucet Seat wrench
Shower wrench set
Crescent Wrench - not too big, 6" or 8"
Four in one Screwdriver/ 2 sizes each of Phillips and Flathead and a 1/4" nut-driver. Handy as a pocket.
There's more, but these will get you started in most USA kitchens or bathrooms.
I'll let others chime in with more.
Note: Buy good tools. To quote my Dad : "Buy cheap, buy twice."
Joe(also remember -- it's Righty Tighty/Lefty Loosey)Nation