I won't be of very good advice because Peppito and Jasmine are used to travel with me (car, plane) and they enjoy staying in a new place as long as their purrents are with them

But I would say that the best would be to have your neighbour come in your, sorry, Fister's appartment instead. Or you could test before your holiday and let Fister go there for a day or a week-end while you are here and you can visit him sometimes.
Good luck for this new adventure