Chanced upon your t blog... I was in my midst of finding air con deals as well... And a few days ago, my sis bto Fb group recommended a gain city guy whereby I was quoted 3900 for sys 4 for MIT starmex w g22 copper wire, half inch insulator and 16mm drainage pipes and I managed to bargain for two installation trips too... I find his pricing was reasonable after comparing with some Renotalk recommendations and direct coys... Plus he was still very friendly after answering my plenty of questions and worries on workmanship etc... ( quite kai see mentality, keep on checking and comparing btw quotes) Well, if you are interested, I can pass you his contacts and you can find out more... Hope this helps... Cheers...