Pro Gard hit it on the head, Felco secauters are a must, purchase the most expensive you can afford, make sure they are not too heavy and can slip easily in your back pocket.
Gloves - Lightweight leather, rubbery thorn proof, waterproof, everyday protection. You will replace all these many times but it is great to have protection whatever the weather and garden throws at you.
Spade - get one which feels comfortable, not too heavy or with a massive head. You may move ground in bigger chunks, but you won't be able to move in the morning! Same with the fork. I use a brand with a 'shock' absorbing thing that lessens the dull thud from your shoulders when ramming it into a buried boulder.
Twine, u shaped hooks, hammer, sissors, plastic bendy things to tie in climbers, hankies, lip salve, rain protection, seat covers for your car (when you are wet and muddy) and a flask! Oh, and lipstick. x
Depends what work you want to do and what comes your way...I am another that buys cheap secauters as clearing big borders this time of year creates a lot of waste..it just swallows tools up unless your vigilant !!
I have found a 17lb metal post hole digging bar very useful to cut through roots and remove shrubs & small trees. I now rely on my spade & fork being very strong the makers name has worn off but I think they were Bulldog ? I also carry a mattock if the ground is unwilling to yield. folding tree saw & a long reach lopper are all handy too...
Blimey come to think of it I couldn't do without any of the stuff I've got
I tended to build up the tools as the jobs arose.
Anyway all the best with it..
If its garden maintenance
A good petrol blower
A good mower not one from B+Q it will fall apart in a year
All the hand tools, hoe e.t.c e.t.c
Secauters like pro gard said the best by far are felco but cost the earth and if you loose a pair a month like me then buy c.k ones there half the price and nearly as good.
I think if i was left at a job on my own thats all i would need
hope it helps
whatservices do you intend to offer?
As a start for ten, Regarless of the above a pair of felco secauters and a silky gomatro.