Cavaliers are very adaptable dogs, I'd say she'll do alright! It's a good idea you're taking her there to familiarize her before the move. Although I would be concerned about not having a secure garden, is there a way to get gates or a fence for it in the future?
The advice about getting a walker is a good one, get someone you know and trust to pop in in the middle of the day to get her out for even 20 minutes for a quick stroll.
Desrae, guardian of two tri-coloured cavaliers, Belle 3 years old and Bobby 1 year/8 months.