Figuring out how to get to/from places in & around Dublin involves more than a pinch of black magic - if in doubt, ask a local!
The Dublin Transportation Office has a very handy Journey Planner for short (walking/cycling) trips - it's well worth using.
Generally, round taxi fare up to the nearest Euro if it's between 10 and 15 Euro, add a Euro or two if it's over that.
Restaurants will usually add 10%-15% to large parties (usually, over 8 people). You're not obliged to pay this, but you should, unless the service has been particularly bad, or there's been a major problem, in which case you really should let management know, and give them a chance to sort it out. For smaller groups, 10% is a fairly standard tip, 15% if you thought the service was particularly good. More than that would be pretty unusual.
It's not usual to tip at the bar, but if there's a waiter service, generally round up to the nearest Euro (for a single drink) or add a Euro or two if you're buying a round.
Ireland has a fairly mild climate. However, climate is the average of 30ish years of weather - so be aware!
Expect some rain - in general, if you leave your umbrella at home, you're guaranteed rain. This counts double for anyone in white linen trousers! Usually, these showers won't last long though, so serious waterproof gear won't be needed.
Temperatures in June can range from 5°C to 20°C (40F-70F), but general stay between 13°C and 16°C (55F-60F). Dublin can be fairly windy, which will make it seem a little colder, but a jumper (sweater) or light jacket should usually be sufficient to keep you warm.
A general rule for Irish weather is that if you don't like the current iteration, wait five minutes and you'll have a new one.
It's one of the few countries where it's not uncommon to carry an umberella and sunglasses with you at the same time
We drive on the left hand side of the road. Please join us in observing this custom.
Taxis are reasonably plentiful during the day, but can be more difficult to find late at night, particularly once the pubs start emptying, and later, when the clubs do the same. You can book a taxi in advance at the hotel reception - this is especially advised if you need an early morning taxi (for example to the airport).
The 46A is about the most reliable bus service in the country, and stops right outside the hotel. Ask the driver for the hotel when you're getting on, and he'll let you know when to go off. You won't get change on the bus, although you'll be issued a 'change ticket', which you can then exchange at the central office on O'Connell St. You can only pay with coins - fare is 1.35EUR from the city centre to the hotel.
It's possible to get on the Luas without a ticket - but don't. There are inspectors just too often, and the fine isn't worth it. Luas is mostly useful for those wanting to go shopping - from St Stephen's Green, take it out to Balally, for the Dundrum Town Centre.