Buying a house in summer in Spain may sound crazy because with all the tourists around you probably think prices went up, ant they probably will go down in September. It is true to some point. Some owners and companies expect more demand in summer and put the prices a bit higher.
But consider as well that many properties that in winter are not in the market, now they are. That many owners that come only in summer, are at their houses for sale, which can be an advantage. So I will say that the number of offers is higher. And that can be good for you if you know the market.
It all come to the knowledge of the market. If you know well prices, and what you want, then the time is right. My advice will be to explore the market in Summer. If you find the perfect deal, buy it! if you think the price will be lower in Fall, wait for the right moment to make an offer. So if you are thinking of buying a house in Summer in Spain, at least have a look around, there are plenty of offers on the market.
Cristian de la Torre