I aim for €300 per day and rarely work more than 6 hours a day.
I rarely reach that target,.. but I would consider £30 per hour reasonable & do-able on most days,.. not every day, but most days.
It sounds like a lot of money, but by the time I pay VAT, TAX, Income levy, Pension Levy, Equipment costs, Vehicle costs, accountant fees etc etc, I actually take home about half of what I earn.