> What does the existence of the futures market allow me to do that I can't already do in this scenario?
Leverage.
So I had a look at live data for an example. As of writing, 1GBP = 1.28 USD. Let's look at some example scenarios, assuming I believe 1 GBP will be worth 1.41 USD (+10%) in 3 months and want to make as much money as I can with a $100k investment.
- I buy USD from a regular bank or currency exchanger and wait 3 months. If the price goes up 10%, I make $10k. If the price goes down 10%, I lose $10k. If nothing happens, I lose nothing.
- I buy GBPUSD futures contracts. I need $7346.25 margin to open the contracts and $5877 to maintain them (per https://www.interactivebrokers.com/en/index.php?f=marginnew&...) and I control 62500GBP ($80k) per contract. With $100k, I can buy 13 contracts and control $1.04M. If the price goes up 10%, I make $100k. If it goes down 10%, I lose $100k.
And then, for fun:
- I buy 86 options for a GBPUSD futures contract at a strike of $1.28 for $99k. If the price goes up 10%, I make $593k. If the price is at ~$1.30, I lose nothing. If the price is below $1.28, I lose $99k.
I'm no expert on futures however so there might be something wrong here, though the answer is definitely leverage.