I am guessing here but you are probably suffering from product-market misfit here. Most probably your clients' needs could be served with a Wordpress install, a few plug ins and a shiny theme on top. They would happily pay £300 for that and you can still make a decentish profit.

You are providing a service at a tick higher level than that, which they don't really need. I guess you see where I am going with this; you need to find clients that actually need your skills.