Bad Service, I would like my money back

Kandua claim to have vetted their tradesman before sending them out to you to undertake a job & also state that these guys are fair. I appointed an electrician to sort my houses electrical faults, the guys Padington & Sheperd arrive 2 hours late for the 1st appoint, they quickly reviewed the job requirements, gave me an estimate costing for spares & labor the R4300, I paid them a R2000 deposit in order to start work (how do these guys run a business without a cash float??) they came in to commence work, whilst they were in operation they informed me that my DB Box was wired incorrectly I informed them to make the total R5000 & fix up everything, they completed the work in my dinning room & living room & left out the 2 smaller rooms, as I am paying them they inform me that the price is more than R5000. I did some calculations on the pricing that gave me for the spares , I found out that there is 120% mark up on the original price for the spares that they used. The dimmer modules were not working that evening so I asked them to come back here again they arrived an hour later than confirmed time. They told me that the dimmer connections were faulty to which I responded that they should replace the dimmer switches (R800 per switch) with normal ones, I assumed that I would get back the R1600 I paid for the dimmer switches & this will be used to replace the switches in the lounge & my 2 bedrooms on my calculation for these this would R360, I also assumed that my total will be reduced due them replacing the defective dimmer switches. In total I paid them R4000 (they wanted cash, again as a business how do you not accept EFT payments) . They phoned & harassed me for the additional R1000 stating that the switches that replaced the dimmer modules were the same price, there was extra work in removing the faulty parts to install the new ones( when I send my car in for service do I pay to have the broken part removed), they also threatened to come to my complex disconnect the electronic gates & lights to get their money. This experience was really negative, Kandua I would like my R1200 refund..