Unacceptable behavior

Highly unprofessional! Gave them my s****** and asked for them to check everything as my wife drives it to work and back asked them to please take good care of the bike, get told to come fetch the bike as it is “ready” I arrive on site and pay my invoice to be told oh sorry the exhaust is damaged and will cost an extra R1500 with fittment to repair (1st issue they should have given me the option to repair before collecting)!!! I then take the bike because we need it to get mrs to work, the mrs drives the bike a total of 5 days and the s****** sump plug had come loose (obviously not tightened properly) they oblige and come fetch the bike leaving us without a bike for another day, he brings the bike back the following afternoon and we drive the bike another week and the bike breaks down again, I take it back to them (bare in mind I am self employed and every hour counts for nothing) I drive it all the way from kommetjie to lakeside and drop it off and say to them one last time they must fix it properly! We agree on a price of R1500 for the new exhaust and includes fitment, they tell me the following day (today) that it is ready for collection and send an invoice of R2545, a whole R1045 more than what we agreed on???? Then they want to argue that their service has been impeccable??? Your service for your mistakes has been great but a good service provider will not have to service their mistakes!!!! Highly unsatisfied and highly don’t recommend this business!!