Me, me and me!
If I had limitless money and resources, heck I'd replicate his entire castle!
You would need a lot of money and resources, but not limitless money and resources. LImitless means infinite.
The castle in the original matte painting loolks like it might be 100 or 200 feet long.
https://memory-alpha.fandom.com/wiki/Rigel_system?file=RigelVII-Holberg917G_fortress.jpg
And the remastered building was much larger.
https://memory-alpha.fandom.com/fr/wiki/Portail:Arts?file=Holberg_917G_fortress%2C_remastered.jpg
The archway thing on the rock between the two segments of the bridge seems to be about 15 times as tall as the railings on the bridge, which shoul d be about 2 ot 4 feet high. Thus the archway thing should be about 30 to 60 feet high and about 25 to 50 feet wide..
There are two similar looking structures on each end of the building facade facing toward the bridge. The total width of that facade, including the arch like strurctures is about 3.75 times the width of each arch structure, and thus should be about 93.75 to 187.5 feet wide. It is also about the 3.75 times the height of the structures, and thus should be about 112.5 to 225 feet wide.
The facade between the two archlike structures seems to be about 2.25 divided by 3.75 as wide as the total width including the two structures. So it should be 0.6 as wide as the total width including the two structures. And thus it should be 56.25 to 112.5 feet or 67.5 to 135 feet wide.
The facade between the two archlike structures seems to be 5 or more stories high, and about 2.25 times as wide as it is high. If there are 5 10 foot tall stories the facade is 50 feet tall and 112.5 feet long between the archlike structures. If there are five 15 foot stories, the facade is 75 feet tall, and 168.75 feet wide. If there are five 20 foot stories, the facade is 100 feet tall, and 225 feet wide. And the total widthof the facade and the archlike structurees would thus be 187.5, 281.25, or 375 feet wide..
There are at least 21 windows in each of the upper three floors of the facade between the arch structures. Architects would describe ithe facade between the two archlike structures as as al teast 21 bays wide. If each bay is 5 to 200 feet wide, the facade of 21 bays would be 105 to 420 feet wide. And the entire facade including the two archlike structures would be 175 to 700 feet wide.
Combining al these calculations, I get the impression that the total width of the facade facing the bridge is proably about 187.5 feet.
Assuming that the building is 187.5 feet square and has no courtyards or light wells, the building would have a footprint of 35,156.25 square feet (3,266.1225 square meters) feet) and a total floor space of 175,781.25 square feet.(16,330.6125 square meters) on five floors.
That is similar in size to the largest house built in the USA, Biltmore, in Ashville, North Carolina which listed with 178,926 squae feet or 16,622.8 square meters. Of course if Flint's house has has many light wells or courtyards, it might be a lot smaller than that.
https://en.wikipedia.org/wiki/List_of_largest_houses_in_the_United_States
And if the facade facing the bridge is as wide as 700 feet, and the building is square, and has no light wells or courtyards, it will have a footprint of 490,000 square feet (45,522.4896 square meters) and will have a floor space of 2,450,000 square feet (226,612.448 square meters) on five floors.
And that would make it a little smaller than the Hofburg Palace in Vienna, Austria, which is listed with 2,583,389 square feet (240,000 quare meters) of floor space.
https://en.wikipedia.org/wiki/World's_largest_palace.
Of course, if Flint's hous ehas a lot of light wells and courtyards, it could be a lot smaller than that despite having a 700 foot facade. And of course I think that the facade was a lot closer to 200 feet than to 700 feet.
The Hofburd in Vienna is hardly the building with the largest floor space.
This list includes the buildings with the largest floor space:
https://en.wikipedia.org/wiki/List_of_largest_buildings#Largest_floor_area
The 60 buildings on the list go from 18,760,000 square feet (1,900,00 square meters) down to 4,280,000 square feet (398,000 square meters) and so there must be a lot of buildings smaller than them but larger than the Hoffburg.
And all of the largest buildings in the world, were built - like all the normal sized buildings - by persons or organizations with limited and finite money and resources. Nobody has ever had limitless and infinite money and resources for an building project or other purpose.
Therefore, you do not need to have limitless and infinite money and resources to build a structure as impressive as Flint's residence.