My problem is. Other than lettering all these cars look alike.
Are they all using the same chassis and bodywork?
Nope each team must construct their own unique chassis. They spends millions of dollars in doing so. Big team budgets are around 200-300 million dollars per year. Toro Rosso is Red Bull's development team and as such would be consider a mid-level team. Their budget would be around half of Red Bulls budget.