I make my living turning wrenches and spinning ratchets. I maintain 60 bucks a week for SO. That is for my personal tools. I also have accounts with various vendors including SO for tools for the shop. Special tools that I normaly wouldn't maintain for myself. Things like special sockets, OEM service tools (john deere, case, kubota), and capital garage equipment like tire machines, lg jacks, scanners and alike. I'm a one man show. If I don't have the tools, it won't get done. I have no one to borrow from, so I have a lot over 25yrs and still aquiring stuff monthly. It all gets written off at the end of the year, I try to spend with in reason, but when you need it and the job completion depends on it, you have to plunge. I also purchase tools to expand my services to minimize sending stuff to dealers because they have the tools to do the job. It can get crazy, but it pays for its self over time.