Recently I went to a frame works shop at Clementi Ave 3 (next to Clememti MRT) to make a piece of frame mat for a watercolour painting. The size of the mat was 68cm x 50cm with a window 47cm x 35.5cm at the middle. The lady at the shop used a calculator, a pad of paper and about 3 minutes to get the quotation. It was $45.00 per piece and took about 7 to 10 days to complete. I was shocked and reminded her that I just wanted a piece of cardboard with a window at the middle. She confirmed it was the price, so I left.
Later I went to Sertra Trading at Upper Paya Lebar Road, the helpful ladies there charged me $15.00 per piece. I cut two pieces, to keep one as spare (shown above).