I don't suppose plots of land will be very cheap nowadays and getting someone to build a house for you can be a bit hit and miss I suppose.
My friend needed an extension built on the side of his house and the price Quoted was very high.
After a few moans about the price being charged and a bit of bargaining the price was reduced by over 33% to something that he was willing to pay.
Once again word of mouth or recommendations is a must.
Now I have never ever tried it but shopping around for for the best price is not always the best but it gives you the idea as to how much it is going to cost.
Also make sure there is building permission or you can get it before you buy any land.
If you watch Cowboy builders on the T/V it would put you off.
And remember the Wellie Boots and Umbrella if going up near Dunoon.