score:5
Ferry bookings work in the same way as flight tickets these days, the actual fare depends on the date and time of the booking, and changes in time.
To check the fare that is of interest you need to go to the ferry company website, e.g. Stena Line, enter the dates, press continue booking, enter the number of passengers and the size of the car, and then you will have all possible ferry times with the combined fare---which you can book.
Unfortunately you will have to do similar steps to check the prices of all the other means of transport.
If I have to guess, I would say that the ferry only makes sense if you already own your vehicle. Otherwise, it will make more sense to get to Dublin on the public transport, and rent your car there.
Upvote:3
Rome2Rio gives you the alternatives. Rome2rio gives airfares, but not for the ferry though. You can get a detailed quote from Stena line
Upvote:5
If your preferred option does not work out, you could always try Eurolines Coaches, which depart to many European Countries including Ireland from Victoria Coach Station, London.
More info:
Upvote:5
If you'd prefer to get a train, the cheapest option is generally a "Rail & Sail" ticket: http://www.stenaline.co.uk/ferry/rail-and-sail/
In fact, it's usually cheaper than paying for a car on the ferry (and that's excluding the cost of fuel to get from London to Holyhead).
As well as being cheaper, you also have the peace of mind that if there are any delays, you're still covered for the rest of your journey.
Upvote:9
Because there are some very cheap options on low cost airlines, I would suggest flying as a convenient alternative. Ryanair and Aer Lingus have various flights each day.