The average amount you earn per hour depends on how much you charge AND how quick you do the job. If you charge an average amount and are super fast then £70 per hour is possible. If your charges are high and your work rate is, say, normal then £70 per hour is possible. If you are cheap, then to earn £70 per hour, you are going to have to work super fast ro achieve it.
Of course it would make sense to charge relatively higher prices if you pay particular attention ro detail rather than finishing the job in a fast time. It is up to the individual to decide which way to go.
I once watched a high priced cleaner get over £100 per hour on a domestic job, and was less than impressed with the result and methods. I would have been substantially cheaper, significantly slower, and the result would have been massively better.
My marketing costs, this year to date have been £320.
Pay attention to detail, take the time required to do the job properly without rushing, do an excellent overall job and not just on the more noticeable areas, and charge a fair rate, and your marketing costs will be sustantailly reduced.
Dave.