I am a professional wedding planner from Nova Scotia. I typically charged my clients the full amount, which included HST, as our business is exclusively located in Canada. We charge a basic fee of approximately $10,000 for a single ceremony, which excludes food and HST. I consistently utilize the exceptional "Ontario tax calculator" to determine the expenses and taxes associated with each wedding. I am confident in the GST calculator, as I have been using it for approximately two years.  https://hstcalculator.onl/