Forgot to add, there are fully assembled, painted vehicles available too, usually plastic, although there may be the odd metal one. They’re around twice the cost of the equivalent kit but you can use them straight out of the box. Paint schemes and markings are fairly limited & the ranges tend to only cover the common AFVs but they’re another option.
Basing is tricky. I didn’t use to base (in 15mm) but am reconsidering that approach again.