I know what you're thinking: talking about taxes, BORING! But this is very important to know.
In the UK, our VAT (Value Added Tax) is automatically added to items, and the price advised is the final price we pay. In the USA and Canada, taxes are often added at the end, so the pricing you see on menus or clothes tags, for example, will likely be a partial price. It is important to remember this and that taxes will change from state to state.
Resort fees are another cost that can surprise Brits when they pay for their stay in some hotels across America and Canada – particularly in larger cities. Essentially the resort fee covers whatever the hotel wants it to: things like using the gym, pool and sometimes parking. Sometimes hotels are transparent about how much the fee will be beforehand (sometimes not) so keep this in mind.
Tipping is not so common in the UK, but definitely is in both America and Canada. The general consensus is that 15-20% is standard, but that 20% is preferred, so do consider that when planning food costs. Sadly, many people make most of their wages through tips, so ensure you show appropriate gratitude.