First of all, ask how many weddings a venue conducts around Christmas time, as you ideally want to be their main focus and choose one which limits weddings at this time. Ideally, you should ask for any images the venue has of previous Christmas weddings, so you know what to expect. It would also be useful to know the extent of a venue's grounds for festive photographs and what contingencies there are in place for 'indoor' shots. Once you know the extent of the venue's Christmas style, you need to check if they'll allow you to add any extras for yourselves, such as the addition of presents under the tree, extra decorations in a style of your own choosing, or whether they mind a visit from Santa himself! Another point would be to determine whether the venue is prepared to cater for a full Christmas wedding breakfast to include all the trimmings, if that's what you're looking for. Finally, as the day draws to a close, it would be useful to know if the venue is happy to host a carol concert, play festive tunes, allow party games or host anything in particular you have in mind. Most venues are always happy to do what you want, but it is always best to check.