Restoring a vintage pool - what structural issues should I worry about?

We just inherited a beautiful, very old concrete pool, and while the aesthetics are amazing, the structural concerns are keeping us up at night. It looks like it hasn't been properly maintained since the 70s, and I'm worried about the integrity of the original shell. Before we even think about tiling or resurfacing, what are the biggest red flags we should be looking for? Specifically, are we dealing with major rebar corrosion, or is it more of a simple concrete crack that can be easily patched? Any advice from professionals who have worked on these kinds of vintage pools would be greatly appreciated.