Sailor – so far as I’m aware concrete roof tiles don’t have a protective coating, and don’t need one because as they’re laid on a slope and overlap the rainwater just runs off them towards the roof gutter.
In my opinion, having a contractor climbing all over the roof of your building is likely to crack even more tiles, and the high-pressure washer that they use to clean them will likely provide the equivalent of many years normal weathering.
Paint won’t seal a cracked tile, so I’d suggest that you have any cracked ones that are visible from the street replaced with others from a less conspicuous part of the roof that are equally weathered, and replace those in that less conspicuous location with new tiles.
If your Owners Corporation wants to spend $30K to improve the aesthetics of the building for a few years, then by all means have it painted, but frankly if it’s aesthetics and longevity that’s the objective then look at replacing the entirely of the visible sections with a metal / colourbond™ roof.