Exterior Wall for workshop advice

Hello All,
Wife and I purchased a home on 5 acres and thankfully the proprety has a workshop on it and I am looking forward to spending plenty of “man time” out there. That’s the good, the bad is that the workshop exterior has suffered from years of neglect and is going to require new siding on it.

The building sits on a concrete slab and is wood frame construction. It has two roll doors on it. The problem is that it looks as if the origional owner built the exterior walls on the cheap and used something that looks like OSB board. I suppose this could work, except that they neglected to stain or pain the wood after the initial painting. Because of this the wood on the exterior has aged and there is even a bit of “rot” at the bottom. The “rot” is confined to the exterior boards and has not affected the frame.

I have considered just tearing the whole building down and putting up a new one on the slab. However, after taking a real good look at it today I don’t think it is necessary and if I go that route will just lead to spending a ton of money that I don’t have to. The building is wired for electric, has good usable workbenches in the interior and is dry, no water leaking. It has a metal roof covering the structure, although that roof is flat and not gabled.

The current OSB board that is on the building consist of full sheets so replacement should be pretty easy and straight forward. I can take a standard 8x6 sheet of replacement wood and replace the old stuff that is up there. There won’t even be much cutting to do as they used full, uncut sheets for the exterior walls.

So, here is my question. I would like to do a decent job on it, but watch the money spent as well. My first thought is to replace the OSB with new OSB board and eventually cover the exterior in vinyl siding to match the house. I have even thought about using aluminum siding on the side of the building under OSB, but don’t know much about it. I think that the aluminum can be purchased in 8x4 sizes, but I am not sure. So, here is my thought although I could be totally wrong about how I am going about it, if so please advise. I was going to pull off the old OSB panel by panel and replace it with new OSB. As soon as I get one replacement panel up I was going to stain it with a weatherprof stain to make it water resistent. I realize that this is not a long term solution, but would it be okay to do this as a temporary mesaure until I get the funds to put proper siding up such as the aluminum or vinyl? If it is, how long can I get out of the OSB treated with weatherproof stain/paint?

The workshop is approx. 38’ long by 14’ wide. Any idea what an guesstamite on pricing would be for aluminum siding? Or perhaps vinyl? Like I said, I want to do it right, however like most people I live under the constraints of finances. I can get it done no problem over time, but doing it all at once might not be in the cards. Any suggestion would be welcome. Thanks in advance.

I have even thought about using aluminum siding on the side of the building under OSB, but don’t know much about it.

Sorry, that should have read, “put the aluminum siding OVER the OSB”, not under.