Terrible customer service and unacceptable standard of work from East Rand walling

Unless you are the type of customer that's happy to wait for 3 weeks to have just 12m of wall badly erected (a job that should only take 2 days, max) and being fed constant excuses and empty promises, after you've paid in full, - take my advise and steer clear of East Rand Walling. My impression of ERW is one of bad customer service and shoddy workmanship resulting from ERW making empty promises, not keeping to deadlines, not providing feedback unless being chased, little or no internal communication between rep's and work-teams to ensure customer's requirements are met, and an unacceptable standard of work (the part they did manage to do). On 21 November 2018, I requested to have 12m pre-cast wall erected and 4m of pre-cast wall extended. Total cost of job was R14 460, which I had to pay upfront on 25 November, as the job is less than R20 000. Work-team started on 27 November. Despite detailed written explanation and written agreement on quote by rep, work-team started with wrong design. Had to tell them to stop. Was then informed that the design I wanted, as specified on the agreement, was out of stock and they had to go back and manufacture the slabs we agreed upon. In addition, I had to tell them that the part of the wall they extended was not straight. Sent annotated pics and details to rep. Was promised that all will be sorted, rectified and completed within a week. Followed up -from my side- with Rep on 28 November, 6 December, 10 December, 11 December and 13 December and was each time promised that the work team will be there the next day. Only to be given another excuse as to why they didn't pitch. ERW subsequently closed for December on the 14th, leaving me with a dug-up garden, a half-completed, skew, wall, my money in their (holiday)bank account and another promise that they will be back on the 7th of January. It's the 7th today, and I will have to, again, phone them to find out when they intend to complete the job which I paid them for, more than a month ago.