There is all kinds of tanks you could buy that are rebuildable. I started 3 and some years ago with protank 1 and 2's, rebuilding the heads, they are super easy, plenty if videos on how to do it and you will learn enough to expand your horizons into other tanks. My opinion on another super easy tank to start your building career is the subtank mini with the RBA, they too are super easy to learn to build on and have a lot more variety of builds you can put in them compared to the protanks. Healthcabin has the Subtank kits but they are white for 7 bucks and that includes the RBA but normal price for subtank kits are over 25 bucks. Plenty of other drippers and tanks on sale too Make a account and get 5 bucks off, first order another 5 bucks off and then 20% off the entire order. Well worth looking into to get started but wait a couple weeks for delivery cause it comes from overseas. I say I scored buying a couple mods and several subtank kits cause the RBA alone is priced over 7 bucks at most vendors.