I would use our ice cave entrance feature-see pic. This comes in 2 halves (front and back) and is made of fibreglass. Will go through a double door. Then have say three Christmas trees outside this 8'/7'/5' covered in snow and dressed with white pealightsto finish this off. We have a finger post (sign post) that points towards Santas Grotto. Our snowman can also stand guard. Inside this entrance-if you create the walls ?- or we can supply starcloth, we then have The Elves workshop comprising small house, small chairs made from large pencils, oversize paint pots with paint brushes and crayons.Plus piles of presents. Finally Santas room- we usually use our Large christmas card backdrops as walling with piles of presents at the base, a free-standing large fireplace with mock roaring fire and stockings for each reindeer plus a large throne for Santa to sit on. An alpine sleigh is available for photo-opportunities or as a base for presents.