Thank you Mike and Jane. I believe I've resolved the concern.
What am I missing? My approach is backwards. It makes sense and adds up from the perspective of the guest. I have set the base price at $300 per night. AirBnB advertises the unit for $395.00 per night. The only other fee is AirBnB’s take of 14%, on which the tax is 7% PST and 5% GST, no MRDT.
Tax on base price (8% PST, 5% GST, 3% MRDT) = 16% x $300.00 $48.00
AirBnB fee = 14% x $300.00 $42.00
Tax on AirBnB fee (7% PST, 5% GST) = 12% x $42.00 $5.04
$95.00 (Gov’t eats 4¢)