I want to buy some land in the country and build a house with strong walls and good vantage points and fields of fire. Preferably with numerous rooms and maids. Also it has to be able to provide power for itself, to have blacksmithing facilities and a metal lathe with maids that know how to use these things. Preferably the house will be located close to strategic resources but otherwise I will just have to keep in mind where they are for later. Also it has to have horses and cows and be close to a forest. Also an armoury filled with weapons.
Once society collapses I will arm the maids and we will search for survivors to press-gang into the service my duchy, the maids will act as officers and the serfs will be allocated to them. One maid is going to have to be responsible for having her peasants cut down the forest to build houses and such for the city that will be built around my house. Other maids will be given military commands and patrol my area for intruders, if food production allows they will be press-ganged otherwise they will be shot. From there they will be send to secure strategic resource and build outposts at these locations and to secure lines of communication to the capital. After the strategic locations are secured farming outposts will be built to increase food production and thus potential population, all the while the outposts will extend my realm. I don't think we have fuel nearby so I have to rely horses for cavalry and logistics. The metal working facilities will be important for producing and maintaining arms, potassium and other resources will need to be secured to produce gunpowder(or black powder if things are desperate), the forest will be important for paper production as well(to issue orders with and to record things). Metal working facilities will also be needed to produce coins, the coins will be backed by the grain reserves of the state and will become the only reliable currency(as no sate will exist to back the currencies of other realms). Thus my currency will be the dominant currency of the world and all trade will be centred around my realm. As we expand we will tear down the ugly suburban houses to replace them with attractive ones, we will also remove all gumtrees and genocide marsupials(as well as ugly people and people that I don't like). Once oil is secured expansion will be rapid, we will be able to build cars, planes and ships to expand to all points of the world. The various conquered lands will be awarded to the most loyal maids to administrate and the maids are not allowed to have children, my own children will be the only blood line permitted amongst the aristocracy so until that dynasty is created the land that the maids control will have t be inherited by other maids.
This is my doomsday plan, I just need to get the land first.