RV Repair: Aluminum Siding Water Damage, aluminum siding, aluminum sides

Question
I am looking at purchasing a 1994 Holiday Rambler Endeavor motorhome.  It has what the owner calls "electorlysis" damage to the aluminum siding on both sides of the rv.  He describes this damage as pea and quarter-sized bubbles on the aluminum siding in some spots and one bubble has a hole in it.  The owner explains that this was caused by a leaking roof which he has sealed some time ago.  He says there is no further leaking.  When asked about repair, he said he took it into a shop and they wanted to replace the aluminum sides but it was rather costly.  He stated the rv is structurely sound.  

Is this something easily repaired?  Costly to repair?  Should we steer away from purchasing this?

Answer
Replacing would be extremely costly.
Take it to a body shop and see how much it would cost to sand and paint. They might even be able to match the paint and repair only the bad spots. I see no reason why you should need to replace any metal.
I hope this helps you out,
Dave

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