Under quoted

I asked for a quotation to replace the chain and gears on my road bicycle and received a quote totaling R2 950.00. After accepting the quote I was asked for a 50% deposit (R1 475.00) which I paid. They then asked me by email if they should replace the handlebar tape as well, which I agreed to. The extra cost for that amounted to R220.00. When I collected the bike I was presented bit a bill of another R2 795.00. An extra R1 100.00 to what I expected according to the quotes received. Not cool at all.