I was asked about the salary, results from generous companies:
1)one job offer, I said about xx/hr (average salary) would be fine---to the company/client directly, the agent negotiated with the company/client, I got xx+15%. work to contract ended.
2) the next job offer, the HR asked whether they should match my last salary, I said "not necessary, since after tax, no much difference" I got the matched salary.
When they want you, you will get the market competitive salary.