Ski maintenance is relatively easy and fun to do and quite cost effective once you get going. But you definitely need the right tools, equipment and workspace.
So starting off you want a waxed ski with a sharp edge. That covers 80% of what you need.
#1 You need to be able to affix the ski to work on it. It is impossible/very difficult to wax and tune a ski unless it is in a set of vices and then attached to either a work bench or a portable tuning table.
#2 Which means you need to have a space / garage / work area to do this. Plus, being able to deal with the mess of a lot of wax shavings and melted wax.
#3 waxing iron
#4 plexi scrapers plus plexi scraper sharpening tool
#5 metal scraper
#6 brass brush
#7 nylon brush
#8 edge sharpening tool (s)
The biggest investment are the vices and tuning table/workspace then the iron.
Tognar is a good source also
https://www.artechski.com/
At a minimum Toko universal white wax does a really good job and can be bought in large bulk sticks. Swix wax is just as good.
Check these series of waxing and tuning videos out from StartHaus. I found them to be quite helpful:
https://youtu.be/u-HkPtILe4k