A 3 month old lamb I wouldn't pay more than $50 for.
I guess quality is the difference, since these lambs are less than 3 months old.
You get what you pay for most of the time
I usually get $130 -$150 per lamb, and have been getting that price for 5 years now.
Auction barn lambs are someones rejects, so those prices dont really apply, unless you dont mind not knowing what youre eating.
Mine are pasture raised with no medications