Salary
100,000 RMB/month is an extremely good salary. It is so good, that I have to ask you what business are you in. Because most people don't make that much. Company owners don't make that much. Senior Engineers with 40 years of specialized experience don't make that much. It is equivalent to $16,000/month in USD.
You might be misinterpreting the actual value. Salary rates for positions in China is a pretty regulated system. The rates are published and known to all. Download the Robert Walters PDF and compare. You can get it HERE, and HERE for a different opinion (same values though).
As you can see HERE, the only people who are making that kind of salary in China are Bank owners and directors at the highest levels of the "food chain". Since you have just got married, I can assume that you are young. The amount that you specified simply does not agree with conventional values. Because the value you posted is so outrageous, I would suggest the following are possible reasons for the discrepancy;
1. The value you quoted is wrong. It is either a typo, or a misunderstanding. Alternatively they promised you "the moon" to get you to accept a position. Saying something like "If you are good, you COULD make up to...".
2. The value you quoted is correct. In which case you are being asked to do something particularly dangerous or illegal. My guess is that it is a lie and you will not see anywhere near that amount of money. It sounds like a Nigerian (419) Scam of one type or the other. Go HERE to find out more.
3. You could be lying and it is just "click bait". No need to do that here. Mostly this is a forum for use by expats to get help that is often difficult to come by. The "like" icons are for administrative use more than to provide any kind of revenue for the user.
I would suggest that you take a good hard look at what they are offering you. My guess is that the figure of 100,000 is either $100,000 USD/year or 100,000 RMB/year. If it is in USD, then the amount of money is quite generous. As the cost of living in China is substantially lower than that of the USA. If the amount is 100,000 RMB/year then you are looking at a standard Chinese salary. This is the salary for entry-level Chinese university graduates.
All expats should look at a salary range from 10,000 to 30,000 RMB/month. You can get offers less than that, but you don't need to accept them. There are more than enough places that will hire you for more. The normal range is from around 15,000 to 23,000 RMB/month depending where you live and what you do. This will provide you a very comfortable life.
Taxes
As far as taxes are concerned, yes if you are an American you will need to pay double taxation. You will have money deducted from your salary for Chinese taxes, and then you will have to give from 40 to 60% of what remains to the United States government. The good thing is that you will not have to pay state taxes, you will only need to pay federal taxes.
Taxes in china are proportioned by income. People who pay less than 5,000 RMB pay little tax. People who are paid around 20,000 RMB/month pay much more. People who pay around 40,000 pay much, much, much more. People who make more than that don't pay taxes, they have creative ways to hide their income.
If your monthly salary were to be $100,000/month in Shanghai, I would suggest you hire an accountant.
Summary
Unless you are a star quarterback, a famous singer, a really hot programmer, a hedge fund manager, or a very pricey hooker, it is unlikely that the amount offered you is legitimate. Best luck in what ever you would do. If I were you, I would walk away from this scam and not look back.
