I reckon I invested about 12 - 14 grand to get myself properly up and running. This included a van that was under 3 years old. I bought stuff that was more than I needed at thew time because I could see the potential for having to upgrade within a year or so and I didn't want to do that. I paid others to do much of the work for me bevause I didn't know what I was doing. I feel that I paid a fair price. Others made some profit from me so that I could make more profit from my customers. I've no problem with that. If I had tried to set it all up by myself, it would have taken me far longer and there was the potential for many more mistakes. That would have used up time when I could have been earning money. Now that I've learned more about WFP and it is all set up, I am capable of doing most of the work myself to maintain my business - which I do. I'm not above calling in hired help if needed though. I'm not so keen on doing electrical things (particularly if it involves 240 volts) so would get help for much of that stuff.
I got a fair deal IMO. I make a lot more money than I used to. The money I paid out to get started has meant a lot of tax relief so far (the bill for extra income hasn't kicked in yet) and I didn't have to pay any tax in January as my allowance for capital items was pretty high (I have some to pay in July though).
If I had been a proficient DIY person, I would have done more of the work myself but I'm not. So long as I can do bits of maintenance on a system that is already set up, I'm OK with that.