Well, a Pacific Tram Keep was recently auctioned off on this site for 105 mil. That's quite a bit above average, but must be considered.
A Tram 18 x 18 on Atlantic will fetch 20 mil more in a desirable location. I've been offered 50 mil for my Malas 17 x 18 on Atlantic. Castles on Atlantic almost never sell for gold, usually sellers will only accept cash. I've seen Keeps sell for 80 - 120 mil.
I know I paid 35 mil for my Fel Keep on Cats a little over a year ago.
So I believe prices on Pac and Atl would be higher, not saying you couldn't find deals and much better prices.