Details from memory-
The Crimean estates (Imperial):
1. Livadia:
A) The Old Palace (built by Ippolit Monighetti in 1862-66 for Alexander II, pulled down in 1909 to build Krasnov's White Palace for Nicholas and Alexandra)
B) The Maly Palace (built in 1866-68 by Monighetti for Tsesarevich Alexander Alexandrovich and his family, burned in WWII-the site is now a tennis court)
C) The White Palace, built by Nicholas Krasnov for Nicholas and Alexandra 1910-1911, now a museum.
2. Massandra, purchased by Alexander III, still standing-the Palace is now a museum.
3. Orienda, built by Nicholas I as a gift for his wife Alexandra (designed by Karl Friedrich Schinkel, adapted by Andrei Stackenschneider in 1852, burnt 1881. The small wooden dacha used by the Konstantinovichii family is still there as are the ruins of the old palace) Purchased for the Crown in 1894.
4. Dulber (designed by Nicholas Krasnov for Grand Duke Peter Nikolaievich, now a resort)
5. Tchair (designed by Krasnov for Grand Duke Nicholas Nikolaievich), now a museum
6. Kichkine (designed by Krasnov for Grand Duke Dimitri Konstantinovich, now a resort)
7. Ai-Todor (built for Grand Duke Michael Nikolaievich, burned in WWII)
8. Harax (built by Krasnov for Grand Duke George Mikhailovich, now a hospital)
The Yusupov Estates:
1. Koreiz (now a resort)
2. Kokoz (under restoration)
3. Estate at Balaklava (don't recall name or fate)
Also, aside from a number of other estates like Alupka, don't forget the Emir of Bokhara's Palace in Yalta, by Krasnov, which is still standing and now a museum.
Greg King