Sockets, MOLE GRIPS, Adjustable spanner, spanner set and screwdrivers are a good start!
cordless drill (fair to good brands on all tools or your just cheating yourself)
Sealer gun and silicone, matches, blowtorch, decent torch and/or lantern, hurricane lamp
electricians knife, shrink wrap, gas or mains solder iron and MULTIMETER, Electricians tape, wago snap connectors and so on!
http://www.ebay.co.uk/itm/WAGO-spring-lever-push-fit-reuseable-cable-2-wire-3-wire-5-wire-connectors-32A-/111340750667?var=&hash=item19ec6d074b:m:muJW12l83Y37ad3MuRpXlGg