How afraid should i be to remove the vinyl top

I bought the car about a year ago it looks like a fairly new top but I’d rather not have it. I have a small leak at the base of the rear window near the corner. Common spot i can fix with minimal issue to the vinyl.
Are the roofs under a vinyl top usually shot and need replacing or just need a lot of clean up???

Usually there is a lot of rot in the corners on both sides caused by dirt and leaves collecting and capturing water. You can get inside the trunk, lay on your back and look up to see if this is the case.

It can be a crap-shoot, if the vinyl has been replaced hard to tell how much work has, or has not been done. Schrödinger’s cat

Generally, you can eyeball the top at an angle with good light and see if there are imperfections in the surface (which would indicate an older vinyl job). Sometimes just running your hand over the vinyl you can feel any area that’s getting pitted with rust. Other than that, it shouldn’t be a problem except for the vinyl top trim pieces (often with holes in the body for the clips). A re-top job might use the adhesive based trim.