There are many different air conditioning units available on ebay at the moment, no doubt driven by the unusually hot weather we are experiencing. If you are tempted to buy a split type system with indoor and separate outdoor unit be very careful. These come ready charged with their refrigerant in the compressor unit and installation involves connecting the pipework and purging the air and moisture from the system, opening the valves on the compressor and away you go. This process is highly likely to release refrigerant gas into the atmosphere which is highly irresponsible to say the least, and is an offence which you could well be prosecuted for. Secondly, if you are successful and manage to get the system working properly, as I was last year, it may well not work a year later when you next need it. Again, as in my case. The reason for this could be a leakage of refrigerant and my own experiance of this is that proffesional engineers don't want to get involved with these systems. The other possibility is that some moisture remained in the system and has reacted with the refigerant and corroded the valve which switches the system from chilling to heat pump. If this has happened you may as well throw the whole thing away. All in all a purchase which may well keep you cool for a few days this year, but at what cost?. For me it was around £350 for about half a dozen days of cool air in my living room. As they say, "Let the buyer beware"!