The question of 1 is very important. The foreign exchange market is different from the stock market. It has no exchange and is a discrete global trading model. The essence of the foreign exchange market is the inter-bank market, that is, the market where the world's major banks trade with each other. Because the transaction volume between them is large, ordinary investors can't participate, so there are platform vendors. These platform providers have built a bridge between retail investors and the interbank market. Retail investors place orders, in fact, peaceful Taiwanese businessmen are trading, and the platform uses retail investors' funds and bank transactions. So it is the platform that provides you with the margin service, and the margin is temporarily left on the platform. As for the economic bank you mentioned, it is essentially a secondary agent. They are agents of platform vendors, so they charge more commissions.

Your reasoning is a bit complicated. Try to use the general measurement standards in the foreign exchange industry for calculation. Take Europe and America as an example, assuming that the exchange rate is 1 3000, we call one ten thousandth of the exchange rate 1 point. The contract for 1 is 1 ten thousand dollars. Suppose our account is1000000 USD and our deposit is 1%. Now we buy the 1 contract, with a margin of 1000 USD and a margin balance of 9000 USD. Then every time the exchange rate drops by 1 point, our balance will decrease by 10 USD. If the exchange rate falls by 900 points, the margin balance will become zero. These changes will be immediately reflected in your account.

In fact, when the margin balance is close to zero, which is generally around 10, which is about 100 USD, the platform will forcibly close your position, which is called short position. At this point, there is about 1 100 USD left in your account. In actual transactions, the deposit is used to prevent sudden major changes in the market price, and will not be used under normal circumstances. So don't worry about platform vendors.

But in order to win customers, mainstream platforms often take a more radical approach. When the margin balance is zero, they still keep the position of retail investors, and then they start to lose the margin. Taking the above example as an example, the margin balance starts to be negative. Every time the market drops 1 point, the margin decreases 10 USD. When the margin is kept at about 10, that is, about 100 USD, the platform will be forced to close its position. At this time, the account balance is only about 100 dollars, which is completely explosive.

I think the above answers your third question at the same time

If you buy Canada and Japan, the platform vendor actually needs to use the US dollar as a bridge to exchange it twice, so the price difference between Canada and Japan is the sum of Canada, the United States and Japan, or even greater. However, as a retail investor, you need not think too much. These are all made by platform vendors. You just need to know that every time Canada and Japan fluctuate by one point, the contract will fluctuate by1(0.01* US dollar).

However, it is worth mentioning that the bifurcated euro is special against the Japanese yen, because the transaction volume is large, and it is often directly traded without the intermediary of the US dollar, so the spread of this currency on many platforms is relatively small.

I hope I can help you.