Why can not we see the qualifications that the buyers have?

[firthunandsvox]

I will appreciate your opinions very much:

I have had very difficult clients lately:

One of them made an order requesting something different from what I offered and which required more time and a bigger budget … now she does not want to cancel the order because she insists that I do the work. Although she is willing to pay now, I do not want to work for her anymore because those kinds of work experiences end up very badly.

Why can not we see the qualification that the sellers give the clients and thus evaluate if we agree to make a collaboration with them?