There's a difference between a full foundation of mortared and rebar-reinforced blocks and using a few stacked blocks at strategic points to support an outbuilding.
We're talking about a chicken coop. Cinder block Pier 3 or 4 high without mortar will hold a chicken coop easily, if placed correctly.
Her idea of a hill might differ greatly from ours. Like to see a picture of the slop.Depends on what forces its intended to resist.
OP is building on a hill. If there is concern with soil movement downhill, or significant passage of water (I don't know slope on said hill, or peak rainfall amounts), dry stacked cinderblock is unlikely to address those issues. Similarly if there are wind uplift concerns (as in my climate).
Different situations, different solutions. Were it otherwise, we could all be civil engineers.
My oldest coop was made in 2015 and its still fine mine are painted I did have one coop that needed a new floor so had to redo that entire coop and now gonna need to lift it as its sinking into the ground. But id sooner replace walls etc then wasting $50 for a sheet of plywood my coop costed about $100 to make using other woods would be a couple hundred and unless my birds start getting jobs I will still use the cheapest woodI come from a long line of over-engineers (my Dad figured anything that wasn't built to last 100 years was a temporary make-do), and married into a family of over-engineers. If there is a risk of failure that could be averted for a relatively small input of time and money I will recommend the input of that time and money.
OSB will not withstand a wet climate over time.
My Little Monitor Coop had one OSB wall after a miscut of the T-111 resulted in the need to use a scrap of what was on hand. It lasted less than a decade here in the Steamy Southeast despite paint and a good roof overhang.
My oldest coop was made in 2015 and its still fine mine are painted I did have one coop that needed a new floor so had to redo that entire coop and now gonna need to lift it as its sinking into the ground. But id sooner replace walls etc then wasting $50 for a sheet of plywood my coop costed about $100 to make using other woods would be a couple hundred and unless my birds start getting jobs I will still use the cheapest wood
Well my coops are fine so...we all can't be affording pressure treating wood for a chicken coop.
I'm on a "hill" in FL. Only in FL would it be called a hill. Slope varies from near flat to a maximum of about 14 degrees. But I used to do (long, long ago) rainfall runoff calculations for Golf Courses in the "sunshine" state. You'd be surprised what water can do.
Screws have advantages primarily that they are removable much more easily than nails. Their easier removablity is somewhat offset by the time it takes to install vs using a power nailer.
