I am a reasonably serious wine collector and would offer you the following advice.
1. Importing wine into Singapore is subject to duty, however in Singapore the duty is quite reasonable compared to many other countries and is a flat rate per bottle, as opposed to being levied on the value of the wine. Nevertheless, unless you are going to be in Singapore for the rest of your life it would seem logical to only bring those wines with you that you think you will consume while in Singapore otherwise you will end up paying duty on wine which you will then reexport when you presumably leave Singapore in the future.
2. There are a number of proffesional places in U.K and Europe who store wine in underground caverns at reasonable prices.
3. If you ship to Singapore it is imperative that you use the services of a specialist wine shipper (there are a number about) the most important thing being that the wine must be chilled during shipment and especially upon arrival into SIngapore and delivery to your house. Leave a crate of goos Burgundy in a normal delivery van for an hour and it will be good no longer.
4. You will need to have a wine refrigerator to store your wine in Singapore.
5. After shipping I would recommend that you let the wine lay for 3 - 6 months before consuming so that it has time to settle again.
6. You can now buy reasonably good and well stored Burgundy and Bordeaux from a few places in Singapore (be careful as not all are shipped or stored at correct temperatures) but you can expect to pay about 30 - 40% more than from similar outlets in Europe and the U.K
Hope this helps
Hope this helps.