No paperwork, but I had to pay the full (inflated) amount

I had an emergency burst pipe in a block of flats, where I had to shut off everyone's water to fix mine, 17h00 in the afternoon. They charged me an awful exaggerated amount, but I pulled through to make use of their services, as it was late, and the whole block of inhabitants re**** on me for water restoration. When they invoiced me, the amounts was ridiculously inflated (R700+ for a ball valve etc.) to try and justify their big charge. I requested them to give me a better invoice. One that the insurance will accept. I even advised them to rather itemized a call out fee, rather than to charge stupid prices (for offcuts) I had 10 days to submit my insurance claim. I nagged them to give me the amended invoice, as well as a damage report, as requested by the insurance. Everytime they said 'yes' and ignored me further. Up to now, still nothing. Just because they advertised on the internet, that's why I trusted them. Seems like another fly by night service I got.