What is the cost to replace entire eshaust system. It's totally rusted out.

you have used already.approx 500.00 to 600.00 incl catt

On my 1992 Astro van. Replaced the whole thing from just ahead of the cat converter all the way back. Getting all the old stuff off was the hardest part. I had to saw some of the pipes. New cat converter, muffler, tail pipe, connecter pipes, clamps, hangers total cost at O'Reilly and Auto Zone about $250. Did it myself. It takes a bit of ingenuity. The "Original" parts don't quite match up ( The converter was shorter by 6" but I got the same length muffler and tail pipe ) and you can't use the original hangers. I had to drill one hole and put a bolt through ort the hanger just aft of the muffler. I got the cat converter, muffler and tail pipe from Auto Zone on the net delivered to my house. It was done over a two day span, because I had to go back to our local O'Reilly and Auto zone to get the right size clamps and hangers. After the main 3 parts I had to sort of piece it together as I went. Not hard to put together you just can't be in a hurry and be willing to improvise.