Can you still build the older buildings once you unlock the newer ones?

I'm playing sandbox mode in Tropico 4 with the modern times buildings enabled, and as time goes on I keep unlocking more of then.

My questions is once I unlock a certain building, such as the solar power plant, can I still build the thing it replaces, such as the wind turbine?

After some research, I claim that this is impossible. Which makes sense, actually, since the newer buildings should always(?) be preferable.

In case of wind turbines, they are insanely expensive to maintain while delivering only a small amount of power (even on very high ground).

However, I am not certain about the 1-time-only buildings like the Skyscraper hotel, compared to the best other available hotels.

Natively? No. But there is a mod that enables it. You go to the link below, download that file, then create "game" folder in your main Tropico 4 install path then place the contained "lua" file into it. After that, in your new games you'll be able to press and hold "shift" before clicking on the building type menu to enable the older buildings in place of the new ones. Not clicking shift will give you the modern times buildings.

http://forum.kalypsomedia.com/showthread.php?tid=19516