Just got back from HK and just had the hotel arrange a car for me. Ended up being about $500USD each day but worth it given how crowded it is everywhere. If I took a cab it probably would have cost me $200 USD with all the stop and go's and sitting in traffic but not having to wait for a cab, trying to flag down a cab and making sure they spoke english so they would know where to go. I back tracked a few times between Central and Kowloon and a few times ended up just having them circle 2 blocks to my next destination. A cabbie probably would have told me to get out.

Not sure of the company or if its a hotel car but the driver said he contracts exclusively with IHG. Late model S350 with plenty of water.