As others have said comes down to the cost of the siding materials and the labor to put up.
The other factors are tearing off the existing siding, and dump fees
Repairs if needed to the framing. And or additional framing, “nailers” to put up the type of siding being used. You could save a decent about of money demo, taking off the existing side. Rent a dumpster to throw it in.
Estimates, bids are based on the materials and the square footage. You have roughly 1800 sqft to be torn off and replaced. The demo can be just if not more labor intensive if not more then residing. Depends on what it is covered with. So from a labor standpoint you have 3,600 sqft but everything can be done from the ground I assume. So that speeds things up.
T111 is around around $1.12 per sqft. Easy to put up assume if is framed 48" centers. plywood sheets are 8 ft long. You have 9 ft. So 12" skirt boards will be needed. Plus finishing trim boards. Trim boards are more labor intensive and cost a few dollars. How much the trim will cost you depends of what level of a finished look you want. But nice trim can really jazz up a plane building. You might be able to get away with just siding over the existing siding This will save quite a few dollars.
Contractors may not want to do this. It can be problematic and the finish look may not meet expectations. Not the contractors fault but some people can be and are unrealistic and will bitch. Knock the contractor by word of mouth, esp on social media. Not worth the risk.
In my neck of the woods I get my materials from a pole barn building and supply. The sell full “4 quarter” 1 inch X 12 siding boards. T&G or plain edge for board and batten applications. 10 ft boards around $12+ If the building is framed to for board and batten or Board T&G and the materials can be had for around the same price. This is a much better way to go, better look, better wear tear and will last a lot longer then T111. The installation cost shouldn’t be that much more.
I’m not a big fan of T111. It serves a purpose. When I have used plywood I go with faux board and batten look. Put up exterior grade plywood of reasonable grade, acceptable imperfections for cost savings. We’re siding a barn not a house. Cut/rip battens out of 1X boards and nail up every 12± inches. Doesn’t add that much time to the project. Big bang for the buck.
There are cost estimate calculators to be hand on the internet. The numbers given is based on the average cost by zip code. For T111 in my area, around $10,000+_ is the number I got. When was looking for bids to tear off old boards and replace with board and battens on one side of my very large bank barn.Gabled end 70 ft wide rising to 50, around 1800 sqft. Reside with 4 quarter 1X12 boards and battens. The quotes were in the $10,000+ range. That did not include painting.