Hi there Kristine!
There are so many variables to think about. I'm planning a last minute trip for the middle of December as well! Right now, Disney is offering some
special rates for the resort only stays at a discounted price. I would look into that. Then, you could also look into tickets and see how many days you would like to go to the parks. This all depends on your budget. I have been down for just a couple of days and done just an after hours party like
Mickey's Very Merry Christmas Party. It's the least expensive option and you would have a great time.
If you would like to do more, I would pick the Magic Your way tickets with the Park Hopper option. This gives you more flexibility when trying to make advance dining reservations. If you are thinking about the meal plans, I suggest the
standard dining plan. It will save you money over just going to standard restaurants every night. I do hope this information helps you with your planning and if you have more specific questions, please ask away, we are always here to help! Thanks so much for asking the Moms Panel!