Hi, you invest what you can, even if you can't do the full 10,000. I responded to another person having the same question.

The reason you might want to do it via an exchange is because you know the price you will be getting. The exchange that you can buy EOS includes Bitfinex (https://www.bitfinex.com) If you buy via the 8 month ICO, you will be issued a percentage of the 2 million coins released daily relative to what others had invested. It is for this reason, if a big whale comes in on that day you decide to buy from the ICO and spends 100,000,000 dollars, you might end up paying a much higher cost than the assured price on the exchange. But independant of this, you have to be slightly savvy to participate and redeem via the ico, and thus you would be to do it from the exchange.

It is important to learn to secure your coins offline from an exchange once you acquire them. you can do this via a device like a Trezor hardware wallet. I suggest strongly purchasing either this or a S nano ledger, if you have investments. This is because if it is in an exchange, you do not own it, as if they get hacked, that is it.