You can do it yourself. Interesting. Go to the market and buy some pink, white and purple balloons (100-200). Wholesale is very cheap. Then buy a simple pump (if there are many people or children at home to help, the cost of this pump can be exempted), then blow balloons of various colors, tie the intervals of the three colors with long ropes long and strong, without putting up any shelves, and then fix them in an arch shape with ropes at the entrance of the building or the community. Call as many as you need.