Etxea Iin basque means house
Goiko means top as in from above
Anyone with the name goikoetxea would have lived in the highest point of the village - the location of your home was very important in defining who you were
I am afraid the surname is very very common and it's hard to tell where exactly I'm the Basque Country it is from. Escochea seems to be a derived version of goikoetxea
Garai means peak in basque - the surname is from sopuerta, biscay according to Wikipedia ...
Garaikoetxea and Goikoetxea could potentially mean almost the same..