Thank you for all of the replies and private messages! You have certainly given me more to think about as we put in bids on properties and arrange for housing. As always, cost is a concern. However we are fortunate in that we can move up in phases and get one home ready at a time.
Modulars do seem to be the way to go, particularly as they appreciate. The issue is, again, cost.
Because of septic tank placements we probably won't be able to have our ideal situation of the three homes making a mini cul-de-sac with deck work connecting them. However we will be within shouting distance of each other rather than spread across the country as we are now.
Y'all are so nice, we can't wait to come up and be your neighbours!