Cheating clients

Good day

I query the hours charged for this service, your people worked for less than an hour. The majority of the time was used to go buy the taps and also completing the manual invoice.

The actual work took less than a. Hour replacing 2 taps and putting prattley party.

The second issue I raised is I asked if we should buy the material ourselves, the guy then said they purchase and we pay, I asked if we would be issued a receipt of what he is bought from the store so I see the cost he agreed,

When I asked for the receipt these are the discrepancies I found:

Actual cost, -taps 390x2 = 780 - prattle patty 52x3=156 - ⁠total =936 +140.40(tax) = 1076 including vat Your invoice shows material to cost 1346.60 excluding vat

Then I get charged 2035 excluding vat for charging two taps and putting prattle patty around my toilet. They say it took 2 hours to do this. When I asked them why the prices are different they said the company adds a mark up. Why was this not told when I enquired about the purchase of material, I specifically asked before they left and they led me to believe I pay what the shop receipt indicated

And you also charged me for the time spent to purchase the material and the time it took for them to calculate the invoice which was an additional 30 minutes.

How do you explain this gross abuse of your clients where you purposefully delay to over charge your clients