Good booking system, Poor rental service & average car

We waited in line for over an hour before we reached the desk where we were then offered a Volkswagen beetle instead of the Ford mustang convertible we had booked months before because there was no mustang available (it does state or similar but anyone who believes a VW beetle is similar to a Ford mustang is delusional!!). We were then told if we waited 20 minutes we could have a mustang from another hire company (Avis). We waited over an hour then finally went back to the desk and we were told there is a blue mustang waiting for us. We went to collect the car and realised the paperwork was for a red mustang which we found and confirmed with Avis staff was the correct car.. as I went to drive off I realised the rear view mirror was completely hanging off.. we tried to fix it but couldnt so spent ages trying to get help from staff. Eventually someone arranged for a different mustang to be bought over from Avis, this took another 45 minutes, when this arrived it had no GPS so we had to wait a further 30 minutes for this to be rectified.. overall we were there for well over 3 hours which ruined our plans for our first day of our holiday. The car had also not been service as we had to buy engine oil and windscreen wash too plus one of the rear seat belts was stuck! Overall this was a very stressful and poor experience and we will not be booking with Budget or Avis ever again.