Be very careful about buying houses in Gainsborough. You are paying for the Malahide postal address. Unless you are really going to walk to Malahide village from Gainsborough, and it is quite a distance twice a day by foot, then you may be better looking at houses which are technically just outside the Malahide postal address, but, just as far from Malahide village.
There are quite a few houses for sale in Gainsborough today and I have looked at a couple of them with a younger relative (architect) who is in the market. For example, there is an estate up the road, just over the motorway and easily missed because it is partially hidden, called Melesian which is in Swords postal district. The 4-beds on this estate, are superior in build quality and features to the 4-beds on Gainsborough e.g. walled front gardens, better quality red brick, smaller estate (100 houses) with better landscaped trees and green spaces, safer cul de sacs for kids etc. While the 4-beds are in the minority on this estate, these houses are currently a good bit cheaper than Gainsborough, due to the postal address, but, have been rising fast since the announcement of the Metro which will stop nearby. The Pavillions and good schools (Scoil Cholmcille, Educate Together, Colaiste Choilm) are 10 minutes walk, but, not too near to be obtrusive. This is also the on right side of Swords, away from the concrete jungles west of the village.
A lot of houses within the Malahide postal address are a considerable distance from the village. Real accessible Malahide kind of ends at Yellow Walls Road. Portmarnock is a fantastic area for families, or just for the world class beach alone, though the DART can be too far away to walk on Winter days.