sounds like new quarters they have priced you up on and to be completly honest if your keeping it then thats the only way to keep the rust away. If your not then take it to a smaller place and get them to weld in new arches but the difference between the two on quality will reflect on the gulf on the price you will get.
also if your car is radiant red the new quarters will stick out like a sore thumb due to new unfaded paint to your old faded paint