depends on your budget and what you want to spend mate.
I had the oversight of I only wanted to purchase once so i got,
a set of irazolas £22 + vat
fluke t5 1000 £80+
knipex snips pliers and long nose £60 ish for the three
good set of crimps £50 ish i think
ck tool tote £50
hacksaw and junior hacksaw about £25 i think
electricians lock knife ck £6
stanley knife £8
personal preference on power tools but i got the dewalt xrp set with circ saw etc.
head lamp seen these in the pound shops
spriit level long and 1m long
laser level £30 with tripod screwfix special offer
plumb line chalk line both from the quid shop
i now have the metrel 3101 £500 ish i think got a good deal on it again with the meters it`s all about personal preference are you a fluke man metrel man or megger
as i said it all depends on your budjet as you can get a decent set of vde screwdrivers for around a tenner in my wholesalers, snips and pliers can be bought cheaper, tool box needent by as expensive and so the volt tester does not have to be a t5 if you don`t want to spend a ton.
my hammer is anti vibe which was around thirty ish i think but if you don`t want to spend that a hammer will cost you 4 quid or so. some of my gear when i could went on the companys bill so i have not had to pay for alll of it but most of it. i reckon i have quite a few grand sat in the utility room. but all worth it and also a good set of rods, although a bit of trunking lid does wonders as well and a good old fashioned coat hanger