After staying in Singapore for 5 days I came to the conclusion that Singapore was not as expensive as everyone makes it out to be.
It honestly depends on the type of traveller you are and the prices you are use to paying. However, Singapore compared to most other Asian countries is more expensive but coming from Australia it is a lot cheaper than what I was expecting.
Daily cost for everything: $20 (SGD)
Daily cost for everything: $30-$40 (SGD)
Hotel and lots of Activities Traveller:
Daily cost of everything: $60-$100 (SGD)
Get the MRT (train) everywhere, its really cheap! For the 5 days we spent in Singapore we paid about $13 all together for the train (and we used it a lot). Otherwise if your in a central location you can walk to most places as well. Accommodation will range depending on the area and if you want to stay in a hotel or hostel. We stayed in a hostel that was only $15 (AUS) a night and it was cheaper to book it online rather than at the front reception. Depending on where you eat you can get a meal for as little as $2-$3 or if you eat at a fancier cafe/restrauant upwards of $15 (SGD). There is also a range of free activities to do in Singapore, just walking around all day is a great free activity in itself. Otherwise going to any of the theme parks, or more expensive attractions can still be fairly cheap compared to prices back in Australia for the same attractions. In Sentosa they had a special deal to see 3 attractions which was only $80 and there were many other deals like that around the place.
You only really need to stay 3 days in Singapore to get a feel of the city and see most main attractions.