buy a good/accurate torque wrench, ask the truck about trade ins, you do not need the fancy digital one to start, this will be your #1 key tool for being a professional and starting a career. Look after it and it will last you a lifetime, name brand wrenches do hold value pretty decent (if you buy a used one for $200 and keep it nice you can normally sell it for $200)
Sockets - stated above, anything that is not going to fall apart will work for you
hex keys - Bondhus (they make snap ons set that sells for 2x)
Hammers - one that the head wont fly off is the only thing you need to worry about

Screwdrivers - buy a good set (wera, snap on, mac, etc, etc) as rounding out a phillips will screw you over quick
pliers - channel lock are good and pretty inexpensive, move up in quality (if you want) as you wear them out.
Wrenches - gearwrench ratchet wrenches put up with a pile of abuse haha
Ratchets - Gearwrench are fine for you to start, as you have money or they start to get noisey upgrade into what you want (snap on for me) this way you will see what you will use the most and will get the most use out of, that being said once you get 1 good ratchett it is not long until you replace all of them.
As someone starting out my only advice I can give is be thorough and pay attention to detail, these are the key parts that make a good tech. write clear and concise notes as sometime you will have to go back months on a job that might have come back and are blaming you... basically protect your own *** is priority #1

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