You can own a keep in that game?

(No, I have never finished Baldur's Gate)

If you fully upgraded Loire in Terranigma, you could buy an apartment and stock it with the world's cheapest furniture. While it had a nice touch of the salesperson showing you down the show floor, it wasn't a very involving experience, and there was no prize for filling it out but a free inn for buying a bed. You know, if you're the kind of person who plans on spending 1100 gems on inn fees in the last tenth of the game, and only sleeping in one town of the entire game. Really, upgrading the cities in general was more interesting and I'm sort of just mentioning this for completion.

But speaking of games where you upgrade whole towns, you could do pre-set upgrades in Soul Blazer, Dark Cloud 1 and 2 or Azure Dreams, and custom upgrades in Breath of Fire III, but that's not what you're asking!

Heh, I clicked on this thread specifically to mention SWG as well. Even though the game is no longer available (officially), it had some of the best player housing I have seen so far. You could place your house where you wanted, decorate it how you wanted, etc. It was great creating custom little chillout houses with friends or cities. It was also fun visiting other people's houses that were often businesses of some sort (tailors, etc).

I am a little less familiar with Shadowbane, but it was very similar I believe, although maybe slightly more basic. I played the game for a bit but never far enough to get into having my own building or joining a city. I do remember roaming around them though and wandering into houses. I also remember dying in them a lot, I don't think people liked me doing that much.

I really really miss these two MMO's. :(

In the second game, yes.

les bumpos in order to get new suggestions :D

In Divine Divinity, you can buy a house in Verdistis from the head of the Merchant Guild after you complete a number of quests.

You can also buy a house in Treasure Adventure Game.

Not sure if it's been mentioned already but Star Wars: The Old Republic has player ships and 'player bases' have been announced as well.
I really should go through the thread sometime, I really like owning stuff in games as well.
Like the houses and ships in Daggerfall and your upgradeable castle in Record of Lodoss War.

in Divinity II you get your own magic tower!

EDIT: also, Overlord ;)

Or worse yet... postal fraud. Seriously, that is legitimately wrong.

The more I hear about SWG the more I want to play it. Anyone know good private servers I could check out?

In Wurm Online you can actually build your own house. The whole game is all about crafting and building. Heck, I just checked their homepage, the first part of the main description is actually... I guess that qualifies? I played it for a week a few years ago, but only on the free server which had a bunch of limitations (didn't include PvP, everyone looked the same) and where decay would destroy everything you build if you don't log in for a while. It was pretty cool, especially building my own house with a few friends and repaying them by helping them with some stuff they needed for their own camp. You may wanna try the free server like I did to get a taste.

There's a point in Exile 3/Avernum 3 where you can purchase your own house. You can use it for resting, item storage, and it comes with a maid you can talk to. There's a weird curse on the place, though. There has to be a maid there 24/7. Kill the maid, and your party turns into a flock of pigeons or something like that.

I know, it's not the same as all that other fancy stuff MMOs can do, but it's worth mentioning since the Avernum saga has a home here...