It is best to find a professional and responsible company for the first time; If we refuse to sign, it will be very difficult to sign again next time, just like if we go to court and lose in the first instance, we will appeal. If we want to win the appeal, it is equivalent to letting the court admit that its original judgment is wrong and letting the administrative organ admit that it is wrong. The difficulty can be imagined.
After all, the United States is a developed country and has a certain probability of refusing visas. No matter how good the information is, it is also possible to be rejected. We must choose a professional organization to help us.