Solar 8 Must be awoke when doing their job, what is the inspection for if you cant see panels

I called Solar 8 team and asked for an upgrade from 5 KVA solar to 8 KVA, I then had a technicians/sales person coming to my house for inspection and quotation. The person who came says he didn't realise that I have existing solar panels (how so when the panels are seating at the roof of the house? ), they then went ahead and quoted me on the Inveter and two batteries. On installation then they learned that there are existing panels. I was quoted for just the inverter and batteries, now I am told I have to be quoted again for extra panels. Firstly this project took longer than expected, it was meant to be a day's project and it to three days, in the three days there was an inconvenience on my part as I had to pay full grid for power as my solar was uninstalled. I had to incur cost for eskom energy, now I am about to pay for their mistake on not seeing or ignoring that I have existing solar power. The reason I went to Solar 8 was because I wanted to use a professional, preferred Sunsynk service Provider. I am not happy about the fact that they missed such an important part of the installation and want recourse for their mistake as well as refund for the electricity I paid for. I budgeted the amount that I paid based on their mistake and they cannot make this my problem. Grumpy client Phindi Kaunda ***