DentDoctor not professional or customer freindly.

My vehicle was booked for a bumper replacement & spray paint on the Monday. I pre-arranged with the assessor and person confirming the appointment that the bumper and parts listed for repairs are to be pre-ordered and on site on day of the appointment to save time. My vehicle was handed in on the Monday morning (appointment date) at 08:30, and I requested confirmation that the parts were on site as well when the vehicle would be ready for collection. The receptionist enquired in the offices and reverted back with an answer of the same week Friday (5 days later). I contacted the company on the Friday afternoon, only to find out the bumper, which was confirmed as pre-ordered is only now ready for spray painting, that said Friday, and that the vehicle will only be ready the following Tuesday, another 4 days later. I was told that the spay painting was only booked for the following Monday as there were other vehicles in line. I get this, but then why, after specific arrangements, was my vehicle kept at the company for the whole week without doing any work to it, when I would have been able to still use the vehicle without having to pay for alternative transport. Work only commenced on the vehicle the Thursday of that week. Surely this inconvenience should not be passed on to the consumer?