IF YOU FIND THIS TOO LONG, READ PRO POINT 1) and 2).
Dear members of this well-established forum (am a newbie!

) I am a Singaporean in Germany, an avid fan and passionate user of car sharing schemes (one of the earliest established) here. In a year's time I will be enjoying the COE system under the tropical sun again.

I would hereby like to reopen the discussion of car sharing, as a mobility concept, in Singapore. It adds to the spectrum of transport methods available to the mortal Singaporean.
At present there are 3 car sharing schemes (if I am not outdated): NTUC Co-op, Cityspeed, HondaDiracc. According to input from my friends in Singapore, the chief pain of car sharing is the sparse geographical availability of the fleets in the heartland. Waiting in the hot sun for 5 min for feeder bus to the fleet, or cycling (again under the hot sun) there is a complete turn-off. I want my own aircon comfort when I step into the carpark downstairs. The success of the scheme depends on the enthusiasm of the populace. Where I study, there are cars around every block of houses, ensuring instant accessibility. Hence I am here to fish for supporters and learn from the opponents.
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The chief characteristics of carsharing, from my experience, are:
PROS
1) Limiting number of cars on the roads
10000 participants share 2000 vehicles. 1:5 ratio. Need more be said? YES! Remember that the COE scheme was implemented so that Singapore does not erm... drive like Bangkok. So does the car sharing scheme share the same ideal. Less cars, less pollution, more driving space.
But in a Singaporean context, more people have access to it affordably. Empower the masses.

2) Accessibility to wide range of cars
Ideally, there can be many types of vehicles within a pool. SUVs, stationwagons,
Smart cars, sedans. Now you can go Ikea shopping with your own van. Alternative would be to stick to your Corolla for 5 years at $600+ a month.
3) Geographical accessibilityThe Juronger can access the fleet in Bedok after meeting his friends there. And (IDEALLY) return it in Jurong (ask HondaDiracc)
4) Cheaper fixed and maintenance costsInsurance premium, monthly instalment, servicing charges shared.
5) Cost controlBecause cars are charged hourly and per km, you can control how much you want to spend in a month. If you are feeling broke this month, just take MRT lor.
6) No need to serviceHave to take leave just to check that brake light of yours? Not with carsharing. Servicing is done through the employees of the company.
7) Mobility AND privacyCabs sure can get you from A to B. But car sharing allows that in the privacy of your own "cab". Family outings can be done in privacy, no extra ears and mouths in the vehicle. My latest experience with cab drivers had him telling me he ordered his new 3.3L Nissan in September, even BEFORE I closed the door upon boarding. Beat that.
8 ) ProfitableUndeniably, this is another
money-making concept 
for the gahmen. But it is a win-win one isn't it?
CONS
1) Time limitBecause use of the vehicles should be booked for fixed periods, there is pressure on the roads to drive back to the designated lot on time. Watch out!
2) Unavailability of vehicleRelated to the above point. When the bugger returns the car too late, you can't get the car you want. This can be circumvented by allowing usage of a vehicle of similar(or higher) class, and charging the late bugger the extra (+ fine!)
3) Cannot pimp your rideGet what I mean? If not
click here.
4) CleanlinessWell...it's not your own car, so you can leave your Yeo's can and BreadTalk crumbs on the rear seat?

COMPLAIN via telephone hotline and see if the previous user dares to do it again. This requires alot of civic mindedness. Everyone is in the same boat. If not just hire some security guard to check on the vehicle condition upon return.
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If you have followed my thoughts till now, CONGRATULATIONS! Maybe someone can criticise my utopia of having fleets in EVERY single HDB carpark, allowing access, or add to the plus points.
I hope a fruitful discussion blossoms out of my contribution.
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