1. To know if the price is reasonable, you need more information about the version of the lenses and the camera.
2. I know nothing about camera auctions, but a fair amount about art auctions. Setting a low estimate is a common tactic to increase bidding interest. And perhaps your small auction house has little experience with cameras and did no research when setting the low estimate. A lot of people, however, do know the value of Leica equipment, so something like this is unlikely to slip through.
3. The lot of Leica equipment you are describing would never go for $526. Not even the broken M4.
Without knowing more, and assuming the 35mm lens was a less expensive version, the M4 was not black paint, and all the items were in user rather than mint condition, I think $2,500 would have been a bargain for the lot. If that M4 was black paint, and it was in good condition, $4,500 would have been a bargain for it alone, I suspect.
-Laura