Separate prices for build vs upgrade?

I know they have different prices - building a stock exchange from scratch costs more than upgrading from a market, which costs more than from a bank, etc. If and/or how one could go about changing that is beyond me, but I imagine it's all based on the original cost of the improvement, compared to the cost of what you're building it on.

OK, I did a quick test with Humans.

I first researched the entire industrial line.

Then I examined the cost to BUY each one successively, from scratch and as an upgrade to an existing building. In all cases, I had no other factories, and the improvement in question was the only item in the build queue.

Cost to build (in PlanetImprovements.xml):
Traditional Factory = 50
Xeno Factory = 75
Advanced Factory = 100
Manufacturing Center = 150
Industrial Sector = 400

Cost to purchase:
Traditional Factory = 438
Xeno Factory = 690
Advanced Factory = 948
Manufacturing Center = 1482
Industrial Sector = 4368

Cost to upgrade from Traditional Factory:
Xeno Factory = 132
Advanced Factory = 366
Manufacturing Center = 864
Industrial Sector = 3672

Cost to upgrade from Xeno Factory:
Advanced Factory = 294
Manufacturing Center = 792
Industrial Sector = 3594

Cost to upgrade from Advanced Factory:
Manufacturing Center = 762
Industrial Sector = 3558

Cost to upgrade from Manufacturing Center:
Industrial Sector = 3390

So the total cost to purchase an Industrial Sector by first purchasing all intermediate items would be 5016 (vs 4368 for a build-from-scratch).

Out of curiosity, I did a similar comparison but flipped the build costs.

Cost to build (in PlanetImprovements.xml):
Traditional Factory = 150
Xeno Factory = 125
Advanced Factory = 100
Manufacturing Center = 175
Industrial Sector = 50

Cost to purchase:
Traditional Factory = 1482
Xeno Factory = 1212
Advanced Factory = 948
Manufacturing Center = 690
Industrial Sector = 438

Cost to upgrade from Traditional Factory:
Xeno Factory = 438
Advanced Factory = 438
Manufacturing Center = 438
Industrial Sector = 438

Cost to upgrade from Xeno Factory:
Advanced Factory = 336
Manufacturing Center = 108
Industrial Sector = 438

Cost to upgrade from Advanced Factory:
Manufacturing Center = 72
Industrial Sector = 438

Cost to upgrade from Manufacturing Center:
Industrial Sector = 438

Odd result, it would cost LESS to go XF->MC->IS or AF->MC->IS than XF->IS or AF->IS (with my new prices). It seems like if the upgrade difference is below a certain amount, or negative, it defaults to a build cost of 50 (purchase cost of 438).

Nonetheless, I'm glad to see lower build/purchase costs for upgrades.

Out of curiosity, I did a similar comparison but flipped the build costs.

Cost to build (in PlanetImprovements.xml):
Traditional Factory = 150
Xeno Factory = 125
Advanced Factory = 100
Manufacturing Center = 175
Industrial Sector = 50

Cost to purchase:
Traditional Factory = 1482
Xeno Factory = 1212
Advanced Factory = 948
Manufacturing Center = 690
Industrial Sector = 438

Cost to upgrade from Traditional Factory:
Xeno Factory = 438
Advanced Factory = 438
Manufacturing Center = 438
Industrial Sector = 438

Cost to upgrade from Xeno Factory:
Advanced Factory = 336
Manufacturing Center = 108
Industrial Sector = 438

Cost to upgrade from Advanced Factory:
Manufacturing Center = 72
Industrial Sector = 438

Cost to upgrade from Manufacturing Center:
Industrial Sector = 438

Odd result, it would cost LESS to go XF->MC->IS or AF->MC->IS than XF->IS or AF->IS (with my new prices). It seems like if the upgrade difference is below a certain amount, or negative, it defaults to a build cost of 50 (purchase cost of 438).

Nonetheless, I'm glad to see lower build/purchase costs for upgrades. It presents some nice options for making buildings that are more expensive to build but cheaper to upgrade.

I also see that the cost for purchasing a traditional factory and then upgrading it to a Xeno Factory is less than the cost to simply purchase a Xeno Factory. This system is so nonsensical.

Hi!

This issue has already been covered. Check Rush-buy bug/exploit in DA 1.80g thread. To prevent further "loss" of that info I've updated the wiki: Planetary improvements.

BR, Iztok

So what happens to the ((base-spent)^1.1)*6) when (base-spent) is negative, as in my modified example? Sometimes it results in a lower built cost, sometimes it defaults to a cost of 50 (purchase price 438).

Hi!

If you'd read the Rush-buy bug/exploit in DA 1.80g thread, you wouldn't need to ask.

BR, Iztok