There are lots of threads on consulting/freelancers on HN, and lots of great advice. Don't go freelancing lightly, do a bit of reading first, and ideally connect with others in the same jurisdiction for tax/billing advice.
I do consulting and 100/hour (EU/US/CA, not sure for the UK) is pretty average, and 5h/day is a reasonable number of billable hours in a day, assuming not too much time is wasted on sales (and sales can be a billable discovery phase instead, if the process delivers value for the client).
I do consulting and 100/hour (EU/US/CA, not sure for the UK) is pretty average, and 5h/day is a reasonable number of billable hours in a day, assuming not too much time is wasted on sales (and sales can be a billable discovery phase instead, if the process delivers value for the client).