I would complete any major renovation that was required for living in the post modern era. Or at least have all the tools and materials on hand and ready. Out houses will be back in vogue, How many people have that in their list of supplies and ready to go. In today’s world it will be hard for suburban dwellers to get ready.
I suggest buying all the hand tools possible used in the building trades.
Having ten children in the post modern era will be helpful, all boys if possible. 100 acres of good farmland too.