Re: Sutton & Bayside
An interesting question, you might check with Fingal Co Co to see where their area ends down at the coast road. If as I suspect the area where you want to purchase is still within the Fingal Area then your address would be Bayside, Dublin 13 or Bayside, Sutton, Dublin 13 if you're that way inclined. If it's within Dublin City Council then it will be Kilbarrack, Dublin 5 or Kilbarrack, Raheny, Dublin 5.
To walk to the nearest DART station at Howth Junction from the coast road (an uphill battle) can take between 10 & 15 mins. The road is very exposed and it's a nasty walk in the wind and rain. However there are nice wide footpaths on the way up for buggies & wheelchair access etc.
Primary Schools would be Bayside NS which has a great reputation, Scoil Eoin in Kilbarrack (not as great a reputation but good for Special Needs afaik) and then St Peter & Pauls in Baldoyle. St Fintans would be a further walk
Secondary Schools
St Fintans (more male oriented), Santa Sabina (girl only) and Sutton Park (private & they also offer primary education). There is also St Mary's Baldoyle (girl only).
To walk to Sutton Cross from your location would take between 15 - 20 mins, however it's a nice walk along the coast road in the weather.
HTH