It is well known that Singapore is a very expensive country to live in, yes, there is no denying it! However, you CAN survive on the CSN loan which is about 12000 SEK per month (including "merkostnadslån"), especially if you live on campus. I payed about 14 000 SEK for the whole semester for my student room and it was perfect for me. The food is very cheap in and around the campus area (15-25 SEK/meal), however, as you go towards the city it gets more expensive. The local food in the hawker centers was extremely cheap and very delicious! Cheap water can be found everywhere if you don't fancy the warm tap water on campus. They also had water tanks with hot, cold and warm water everywhere around campus and in the hostels, where I filled my bottle several times a day. I know I sound like a mother, but it is extremely important to stay hydrated in Singapore because of the hot weather all year around.
There are a few housing fees you will have to pay during the semester in addition to this, but it is nothing to worry about. Living on campus was great for me since I saved a lot of money and time for traveling and doing things in Singapore. I received one scholarship in addition to the KI grant that you can apply for. If you get a room on campus, remember to double check that you get access to your room when you arrive. In my case this was very convenient since I could go straight to my dorm after we landed.
Transportation is pretty cheap in Singapore, the subway (MRT) card costs around 12 SGD (~70 SEK) and it works exactly like the Swedish "reskassa". However, it withdraws money according to the distance you travel. Unfortunately exchange students were not eligible to buy a concession card (equivalent of a Swedish "periodbiljett").
You can also get around by bus with the same card. Taxis are not too expensive but it depends on the companies and the time of day. I would recommend using the "Uber" app in Singapore and when you are out traveling.
Stay away from the taxis in Malaysia because they are known for driving around for hours before taking their passengers to their destinations, just to make them pay more than necessary. There it is more convenient to use Uber.
Keep in mind that even though Singapore is a very small country, it can take long to travel and walk between places, thus I suggest you to plan your time and consider your options, to save both money and time. You can download the app "Citymapper" on your smartphone to plan your trip wisely. It is an excellent app that shows you alternatives for fast, cheap and heat safe routes.
My biggest expenses were the vaccinations and the flights. I payed a little over 3 000 SEK in total at Cityakuten, though KI covered some of the costs. I booked my flights with Finnair (which I can highly recommend, incredibly comfortable journeys!) and the cost came down to a total of about 10 500 SEK for a round trip. You can get cheap flights through Emirates and Qatar airlines, however Finnair was the best option for me since they have the shortest flight time.
In Singapore they always pay by cash, unless you are in a fancy restaurant or shopping center. Always, always carry some cash with you, especially if you are going out for a day trip. There are ATMs in every MRT station, however make sure that they don't charge you for withdrawals. I got an ICA banken student card which I highly recommend, since it is free for students and they don't charge when you withdraw money abroad.
Finally, it is very tempting to travel a lot while in Asia, since it is close to many exotic cultural places. I went to Bali, Indonesia and Kuala Lumpur and Lankawi in Malaysia. It was amazing and I decided to spend some more money on those trips rather than traveling more constantly. Getting to Malaysia is cheaper by bus rather than plane and I strongly suggest booking any flights with AirAsia (a great budget airline) and Garuda Indonesia (which is a bit pricey but still very good)
It is advisable to be careful in Southeast Asia since there are a lot of thieves. My handbag got snatched by a guy on a scooter in Kuala Lumpur, where I had my student pass, my bank cards and ID cards. Fortunately nothing happened to me and I was with someone, but it is important to keep your belongings safe and maybe carry your backpack in front of you. Leave all your precious belongings in the safe in the hotel room instead of taking them with you.
Also, remember to get your insurance before leaving. The KI insurance from Kammarkollegiet covers you throughout your whole exchange period. I got an eye infection and had to visit several doctors, thus having an insurance was comforting. It is very expensive to visit the hospital in Singapore.