Best rate to buy USDT/Ethereum/Bitcoin?

[GreatArkansas]

I am planning to start a buy-and-sell small business. Which is major on USDT or Bitcoin, Ethereum, and Fiat currency from the Philippines which is PHP.

So I want to ask some advice like what is the best to do for this kind of business? Or like where I can get cheap USDT/Ethereum/Bitcoin then sell it as P2P with my fellow countrymen with of course some spread for small profits.