At a restaurant:
The price of a bottle of house wine (0.75l) => 12 euro
The price of a sirloin/steak meal => 12 euro
The price of a pizza => 6 euro
Typical food => Monkfish with Elvers 22.75 euro / Fillet of iberico pork with plum and nectarine chutney 16.80 euro

At a bar
The price of a bottle of beer (0.33l) => 3 euro
The price of a cocktail => 4 euro

At the local supermarket
The price of a bottle of water (1l) => 1 euro
The price of a can of Coca Cola (0.33l) => 0.8 euro
The price of a can of beer (0.33l) => 1.2 euro

Rent a small car
Rent of car for 1 day => 50 Euro/day
Rent of car for 3 days => 123 Euro
Rent of car for 7 days => 199 Euro

Sources:
http://www.espetadagrancanaria.com/menu.htm
http://www.latojagrancanaria.com/menu.htm
http://www.restaurantebali.com/menu/uk/index.html
http://www.strawberry-autos.com/quotes/quote.php?search_region=Gran%20Canaria
http://www.interealtygrancanaria.com/entertainment_in_gran_canaria.htm