Builders Warehouse review: Customer service

I have been to Builders warehouse two days in a row.
First day I went to the outdoor section and there was no one for over an hour to assist me.
I ended up buying a wrong sized product as there was no one to advise me accordingly.
I had to spend more petrol, money and my time to exchange this.
Again there was no one to advise me, I had to fetch someone from another department who was clueless.

I then returned to purchase more equipment, for a very rude cashier to keep me for a good 30mins at the till to sort out a petty discount issue, while she dragged her feet around the shop looking for assistance.

I had to go to the back to collect stuff and had another hour long wait, only to find the cashier hadn't captured everything.

I went back to capture and pay for those goods and had another hour long wait.

I'm paying my guys by the day and have wasted half a day over incompetence.

A mere apology is absolutely unacceptable.