Yes, Good deals can be had at salvage yards. However, it depends on the salvage yards in your area. I have relocated during the bus reno and my new location makes it a bit difficult to salvage because no one wants to sell used rv stuff for cheap. There are no used rv appliance places around so everyone is clued into the used rv salvage yard thing. Yes, if one is persisatant I'm sure they exist. However, your time has to be worth something. At least mine is.
So, what I did recently is post an add in the local used newspaper (bargain finder, etc....) in the RV section stating that I am converting a bus and am looking for .... and posted what I was after. So instead of spending my time looking for "deals" I had people calling me with things they wanted gone. It worked well.
3 - 70 gallon tanks with sensors, fittings and a monitor for $60.00
charger/converter. tub, antenna, sinks and other things for under $100
The list goes on. The nice thing with this system is I don't have to put the leg work in if I'm not interested. And it's free to me!
So, I know this post has gone a bit sideways, however I thought it should be said. There it is. I hope it helps. Find deals where you can, and avoid paying retail at all costs!