As most of you are aware, my Crius Master D foldie specs are: 52t chainring, 9 speed 11t - 32t cassette, Alivio shifter (mtb) and Sora rd (road).
Please help me to analyse my upgrade options with the most effective, worthy or value for money factors:
1. 9 speed cassette remains. Change to 105 9 speed rd and road bike flat bar 9 speed trigger shifter.
2. 9 speed cassette remains. Change to 10 speed Shimano Zee rd and any SRAM 9 speed trigger shifter. This combination is said to work well, based on online discussions. However, I have no idea whether it is working perfectly or flawless. Considering Zee because it is low profile, silent, crisp, cheaper than Shimano Saint and can use mtb trigger shifters, but it can only be used with single chainring (although I am unlikely to upgrade to 2 chainrings for foldie).
3. Change to 10 speed 11t - 32t cassette, 105 or Zee 10 speed shifter, with compatible trigger shifters. This upgrade is very costly and will waste an almost new 9 speed cassette and chain on top of rd and shifters. I am also not so sure whether I need closer ratios. Perhaps good to have.
4. Go to the extreme and change to internal gear hub. Save all my headaches and fulfil my dream, but should be the most expensive. Not sure about the weight factor though.
Last but not least, I have no idea of the prices for most of these components. Taking CRC as a reference does not reflect real prices at lbs. Importing them from CRC + courier fee + lbs installation fee may end up paying close to the prices charged by lbs, and I have to bear any shipping risks or mistakes made at selection of components. If getting from lbs, I have to ask many shops to compare prices. All these takes time and have to bring my bike there to let them see. I also not sure whether these lbs are trustworthy in terms of pricing, skills and knowledge. Dilemma.
i guess you spend 700 sgd on a bike that you dont like riding ? how can ?
1. the last 105 9 speed is 5500 (now is 5800) they came out in the mid 2000s good luck finding one.
2. I am not too sure if that combi will work.
4, you have to change your wheelset, just that hub alone is around 500 sgd.
you have to know what you want, what isit you dont like about the bike ? too slow ? ride not shiok ?
a way to increase your "speed" is to just have thinner tires. i am currently using a 406x1.0 tire on my mini velo and im able to keep up with road bike easily.
i plan to upgrade it to 10 speed and huge crankset plan to finish everything by feb.
the current specs now is a weird mix but it works (my gf calls it franky or short for frankstein) because i mix different parts to make it work.
currently the specs
shifters: old 8 speed sora shifters front deraileur cables and housing removed as the bike has no cable bosses to run the front d cable
rear D: using the relatively new 8 speed claris deraileur nothing much about it, works relatively well.
cassette: super old SRAM pg 850 cassette, cause the stock one is crap.
chain: some random KMC chain
a
im also using vbrakes on a sti shifters, doesnt work that well but im fine with it.
when you buy a bike, you have to be happy, no point you buy and upgrade again, I done around 2-3 round islands on the mini velo , its not too bad heavy and the wheels are really lousy but okay for the price
(I personally wouldn't pay the lbs to do it though). But since you have just gotten the bike (Assuming) you should ride more before deciding whether it is worth to upgrade. Would getting a better bike be a happier solution. 
