I went scouting for a storage solution provider and lock+store along Serangoon North Ave 4 was the nearest to my home. There are several sizes to choose (12sq ft, 24, 48, 65, 97, 145, 194). Unfortunately, they ran out of 24 square feet room which is the size of a HDB lift. They offered a 48 sq ft room which costs $225 per month (after discount) but I don't need such a big room.
I googled on my phone for another nearby service provider and headed over to Extra Space Asia Singapore at Ang Mo Kio Industrial Park 2. After confirming that they have a 24 sq ft storage room, the sales exec gave me a tour of its facility. I thought their smallest storage solution of 12 sq ft (lockers) was rather small when looking on my phone but it was suprisingly large in person. There are two lockers per column, the lower costing more as you don't have to lift your stuff to put it inside. I wanted a locker but they only have the 2nd level lockers and I didn't want to break my back to carry my stuff up so I stuck to the 24 sq ft storeroom which cost about $120 per month.
I was given a 6 pin code for entry/exit. The facility is open 24/7 so you can go there anytime you like. You would need to get your own lock for the storage door. I also had to buy my own boxes. You can buy the boxes from them for a reasonable price.
Here are some photos of me storing my stuff after signing a 6-month contract:
So did I give a positive review just because I won an expensive prize? Haha... no... I'd say that the prize is just a bonus for me and I'm thankful for winning it! Overall, the experience was a pleasant and hassle free. I may downgrade to the locker size room which is about $80/mth after I have met the minimum 3-month contract duration. There are probably cheaper storage providers around but the location may not be ideal. It's only a 10 minutes drive from my home to the facility. So shop around and ask for quotes. Hope you don't have to spend $ to get extra storage space.