we built a building out of block. I love it, we went with split face block it costs a little more than regular block but I think it looks better. You can also get different colors but they are I think $1.00 or so more a block and to us it wasn't necessary for the cost.
I have attached a few pictures we are finished except for the bathroom, these were taken back in September, I have yet to download any newer pictures. The building is 40'x80' with 14' walls but with the size of the building we figured it would look better than a ton of vinyl siding. I'm not sure if I am 100% correct but the guy who did the block told us that if you are using 2x6's and are required by code to plywood and use house wrap for inspection it is not a lot of difference in price. I am not sure about the costs for supplies in your area so it may vary, if I were you it would be worth checking out and maybe getting an estimate you might be surprised. We have around $40,000 in the concrete (6" slab), block walls, this also includes the I beams over all 5 doors and the metal door jambs. The walls also are poured and rebared every four-five feet (this wasn't necessay by code but we figured with the height of the walls it would be a good idea). There is also a bonus room upstairs, we really don't need the space right now but in the future we would have the space if we ever needed it we couldn't regret not spending a few more dollars on different trusses.
If you have any questions let me know! I could go on and on.