Reincarnated as Richie Rich in Harry Potter world

Author Synopsis:Woke up in a child's body after being hit by a truck? Thank goodness I'm alive! Find yourself in an unfamiliar world, surrounded by communicators, the Holonet, and other benefits of civilization, while everyone around you uses smoky cars powered by burning hydrocarbons? It could be worse. At least you don't have to chase a mammoth with a spear. Did the universe dish out classic transmigrator goodies? Give me a hundred! What, not? Just a couple, but they were hefty grand pianos... That'll do for now. TL synopsis: Previous life-Futuristic AU This life- Richie rich in Harry potter world Evil Dumbledore,Introduces new mageTech at around middle of story, MC is a good guy with a big ego, no harem 1 love interest Family has Damm near Infinite money, but He tries to make his own wealth