Hi, for those bros who bought their own light, do you have good reliable electrician to help you install? How do they charge for each point including cutting of the hole on false ceiling if required? Some quote 10 and some quoted 20 but importantly, I hope to deal with someone trustworthy and responsible... By the way, for those different brands square downlight, seems like for 9W or 12W, they have different cut out size. If when I need to change and can't get back those brand, think will have to waste money to modify he hole again ?