It depends. Are these PAYGO prices or reserved instance prices? There is a HUGE difference. If these are PAYGO prices, the cost would probably be about the same

It depends. Are these PAYGO prices or reserved instance prices? There is a HUGE difference. If these are PAYGO prices, the cost would probably be about the same to have your infra reserved in AWS WITH the added flexibility. This is why not just ANYONE should be able to spin up infrastructure in cloud providers. You should hire someone who knows what they're even doing.