You are only required to leave the flat for about 2 hours after finish and come back to open all windows to release the chemical spray. The process is 5-10 mins. Very simple.
有段時間工作ot關係, 晚晚回家開燈後kitchen 同廳都5-6隻出動, 我試過用殺水劑、小強屋等都無效, 我個kitchen已經很整齊清潔, 工人每晚洗碗後都沬得乾乾淨淨都無用。最後都要花D$請滅虫公司, 之後1-2天, 全屋d小強"死"晒出來,之後我家就安居樂業喇, 雖然要花$, 但好work and can last for long time.