I just replaced the band joist that goes around my house due to rot. The guy that built the place never used any flashing and simply nailed the ledger board through the siding and into the joist. So rot and carpenter ants had their way with it. Luckily the piece was only bad for about 12 feet of the run. But I had to insert wedge jacks as I pulled it out. Luckily I can do that stuff myself with some help from a friend or I am sure it would have cost a few bucks to do.
When I did all my rework with the trim and siding I used the liquid copper stuff on the end cuts and then primed and painted, or stained.
You can see the PT sill board is fine but the non PT joist is all eaten up and rotted. I could stick a screw driver right through the board in spots.