For most of us repeat work is our bread and butter. We have X weeks work and when we finish it we start again.
There is a Cleaner near me who only does repeat work and never takes on new contracts, loyalty to customer.
My view is that you should always have the capacity to take on new work, even if it means loosing some of the bottom end jobs.
That way you can continue to raise prices, your new work becomes the benchmark, and you drop lower priced work, or increace in line with the new. You will loose some jobs, but this should be viewed as progress.
I would say, to the cleaner mentioned above, (if you are full up) aim to loose 20% per year, and aim to gain 20% better paid work.
Keep turning over work, and aim to increase your benchmark.