When you say repairs do you mean to the con roof? Trouble with some is the decorative top on the roof. You could try one of those roof hooks that fit on a section of ladder and hook over the top of the roof but you have to be careful with the decorative top.
As for cleaning try getting a water fed pole. Not the pure water type but one of those that connect to the hose and tap. If the roof is opaque then you can get away with normal tap water and detergents but if its clear they can be a nightmare. If you need to clean a window above the con use an extention pole. Its a bit tricky at first but practice makes perfect and your customers will love you for it! Its true very few think about cleaning and maintainance when they build these things. How many have seen posh conservatories with pealing paintwork on the gutter and facsias above it? As for repairs if I didnt break anything I would pass on it.