For a solo campaign
So my psion is a level 20 egoist (still not completely sure on the build)
She was a human, who then got transformed into an Elan, and she wants a place to live and find her peace without being disturbed when she is not on adventure. She likes her solitude and wants her stronghold well protected from intruders.
I am able to take the Landlord feat and build stronghold and then later reform all 20 levels again. However Leadership, and Thrallherd are not allowed.
Around level 9 she hired a psion shaper to manifest Genesis for her which costed her 6530 gold. Then she spent many days planeshift back and forth between her demiplane and the material plane transferring trees, plants, and grass. Her demiplane is a temperate climate and it has has a lake. (She has Knowledge nature and so studied on how to dig up trees and plants without killing them) Then planeshift, psionic a hired druid to cast plant growth 8 times so that all the plants on her plane would flourish (150gold per casting for 1200 total)
She also hired a wizard to cast a permanent leomond's lasting shelter for 14000gold. She will stay in the shelter until close to 20th level when she has more gold to fund the rest of her stronghold.
When ready to continue her stronghold she will invest in a lyre of building 13000gold take enough cross class preform ranks to be able to play it. She will also pick up fabricate psionic.
Her stronghold design is pretty simply a Cube of Obdurium (the stuff worth double of adamantite) which are augmented to be lead lined, air tight, transparent, ethereal solid, magically treated, and have elemental resistance 60 (to all)
Then there are wooden walls on the inside that make up the rooms and holes in them create windows.
There are 2 rooms, one fancy library worth 2 ss, and a fancy bathroom. Since She is using fabricate and also took craft skills she gets a 20% discount on these components.
The entire stronghold is built on the material plane but is augmented to fly, planeshift, burrow, and submerge at a slow speed. Each room is augmented with a chamber of comfort (70F regardless of outside temperature) , an invisible servant, missing chamber (cannot be scryed on).
In the bathroom is a decanter of endless water for the sink and tub. And there is a bag of devouring for wastes. The library is stocked with master books on knowledge psionics. And there is a shield guardian inside to defend it.
The stronghold is being built in a lawless area and is mobile so 15% discount
leomond's lasting shelter 14000
Genesis 6530
Plant growthx8 1200
Components
Bath, fancy 952gp
library, fancyx2 2856gp
books, knowledge psionics 11900gp
Walls
Obdurium 107100gp
wood walls 1785gp
lead lined 1785gp
Wall augmentation
airtightx3 19125
transparentx3 7650
Ethereal Solidx3 30600
Magically treatedx3 30600
elemental protectionx15 95625
Locomotion x3
Flying 38250
Planeshifting 63750
slow 28050
burrowing 13500
submerging 20250
Spells
Continual flamex4 440gp
phase door 18250gp
Magic architecture
chamber of comfortx3 19125
Hole of hidingx1 2550
invisible helperx3 3825
Missing Chamberx3 19125
Golems
Shield Guardian 90000
Magic items
bag of devouring 15500
decanter of endless water 9000
lyre of building 13000
Total 682573gp
Landlord gives me 800k
so I have 117427 leftover