I often tell beginners to buy decent, but non-bonsai tools. I use a pair of $10-15 florist’s scissors for most of my root pruning. They are sharp and hold a decent edge and can be used for branch and twig pruning as well (a second pair is a good idea). You can buy wire cutters and slip joint pliers at the hardware store (Ryan uses the slip joint pliers). Bypass pruners for garden work will work for initial heavy cuts, particularly since you will be leaving a stub. The first more expensive tool should a good pair of 8" (20 cm) concave cutters like the ones on the Mirai webstore (they are in the beginner tool area but are good quality tools - Joshua Roth I believe. When you decide your wire is too thick for the wire cutters, upgrade to the Knipex wire cutters that are also on the webstore.
I don’t recommend the prepackaged tool sets since they are generally not great quality (unless you spend $300+) and often have tools you will rarely use. Build your tool set staring with good quality tools that meet your needs and upgrade as you go.