Thanks for using this service. Please be logged in to rate my assistance when we are done. Rating 3-5 is good, but 1-2 is bad so talk with me first. Based on the issue you have described there is a very good chance the cooling unit needs to be replaced. Often what happens is gas leaks out of them and then there is enough to cool the top but nothing more as there is not enough gas in the system to cool the entire unit. If they looked at it there are tell tail signs you see that indicate a cooling system failure so I would say based on your issue it sounds like a correct diagnosis. The price is consistent with that repair. You may be able to save a $100 or so if you shop around, but not much more.
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