I’ll be letting my daughter have a go when she’s old enough. She’s only three, so really can’t handle the rules yet. Also, I’ve found that die-cast models and soft plastic figures are essential, since they’re much less likely to get damaged.
Depends on the period you want to do, I guess. I’m doing WWII with my son. I got some die-cast tanks from The Works (£2 each, 20mm scale. They might still have some in stock), with Airfix figures and Hat anti-tank guns.