Invest in the latest Arc PRO. Go Digital with Wireless controllers. Nothing comes close.
This might cost you a bit as you'll need the chips for the cars, some lane changers and some extra controllers. You don't need to chip every car, just buy a few, enough for each racer (4-6), you can easily swap them between your collection. This is known as DPR (Digital Plug Ready).
It might even be better to buy an old digital set, just for the chips, cars and lane changer. They will work with your new ARC PRO!
With what money you have left absorb a load of track from ebay. Plenty of almost new going cheap.