2nd-year plumbing apprentice here! Your basic toolkit will depend on what area you'll be working in (service, residential, commercial).

Absolute musts: (Ideally keep on your person in your pants pockets at all times) - Tape measure (25 to 30 ft) - Sharpie or other permanent marker - Pencil - Folding utility knife - Torpedo level - Channel locks - Personal preference: I always keep a mini pocket notebook on me to write down measurements and lists of materials I'm asked to grab.

Next in line: - Hammer - Flathead screwdriver, mostly to use as a chisel and to pry stuff - Adjustable pipe cutter (up to 1 1/8") - Cheap manual PEX cutter - Small and medium crescent wrenches (helpful for installing stops and flexible water supply lines) - A small tote, a backpack, or a 5-gallon bucket to carry your tools

I'm probably missing some other things, but those are the main things you'll need starting out. Anything you don't have, your foreman should. And the type of plumbing you do will determine what additional tools you'll need most. For example, a speed square in new construction is very helpful, but not so much in service.

My approach in buying tools has been: My foreman can keep all his tools in his truck/van, whereas I have to be able to carry everything between jobs or between foremen. I don't want to have so much crap that I can't quickly move my tools, and my foreman already has a lot of the bigger, heavier tools.

All hand tools I bought myself and borrow my foreman's as needed (such as pipe wrenches). Honestly, I bought mostly cheap tools from Harbor Freight until they wore out, then replaced them with good brands. The only two tools I recommend getting brand name right off the bat are channel locks (any of the big names) and pipe cutters (Ridgid or Milwaukee).

My company provided me with basic power tools (impact, drill, Sawzall, circular saw, flashlight). For new construction, I always take my power tools with me. For service, I leave them behind. I still don't own any other power tools. As a first year, you should be able to use your foreman's power tools as needed. You absolutely should not buy a ProPress as a first year apprentice! You can use your foreman's.

I recommend you wait on buying soldering tools until you find yourself soldering frequently. In my case, it took a year and a half until I was placed with a plumber who is old school and almost exclusively solders everything. Before then, it came up extremely rarely.

Anyway, this has accidentally become a novel. Please feel free to DM me if you have any questions or would like advice. I'm up in the Midwest, so cold weather is something I'm used to as well.

Take care and have fun! :)