I'm really not fond of the Fighters' Guild. If you're just starting out and in need of a steady source of income, it does come with its small perks. It also has a few memorable characters and some good moments, but man, does it take forever to get to them. Near the end of the questline, I got so bored out of my skull that I dropped it like a hot potato and made for the Shivering Isles instead.
While not quite a guild, I absolutely loved joining the Arena. Wonderful characters around every corner, adventure and challenge in every match, plenty of money to go around and a marvelously unexpected ending. You even get to pick out an "Arena Name" for yourself from a goodly-sized list, which most NPCs will then call you by for the rest of the game.
As for houses, there are literally a ton in the game. The handful that I've owned:
- Imperial City Waterfront Shack
It's not much to look at, the neighbors aren't terribly welcoming but honestly, it's probably the best-located house in the game, right in the center of the map, just outside the city walls and not inside a loading door. It's also dirt-cheap at 2,000 septims unfurnished (furnishings are about 3,500 more, depending on your mercantile skill). It comes with two dressers and one chest, more than enough for modest storage needs. Even after I've gone and gotten nicer houses, I still find myself using this one as my convenient alchemy ingredients dumping ground.
- The White Stallion Lodge
An excellent little place if you're passing through the swamp and in need of a place to crash. Totally free as well, provided you do a few quests for the Count of Leyawiin. It also comes with a fun Orc roommate!
- Benirus Manor, in Anvil
A lovely, sprawling manor for a great price (only 5,000 gold! What a deal!), provided that you spend some time dealing with the nasty necromancer in the basement. It also comes pre-furnished, which makes it even cheaper than the Imperial City hovel. As for placement, it's not terribly convenient and I don't tend to spend much time there at all. But it is located in the beautiful Gold Coast region, you can smell the fresh salty air whenever you step outside and rarely is there a day when the warm sun stops shining. It's a wonderful place for an old adventurer to kick back and retire in.
- Duchess of Dementia's Private Quarters, New Sheoth Palace, Shivering Isles
It's a bad, bad place to settle down in. There's a ton of loading doors that you have to go through to get to it, it originally comes with a highly unwelcome bedfellow and I'm reasonably certain that none of the containers are safe for storage. But damnit, I am a duchess and I will live in a palace. And honestly, after decorating a bit with the spoils of my various conquests, the place really has grown on me. It's got some beautiful architecture, is right in the middle of a bustling city, has an excellent garden just outside and has legitimately become my home away from home in the realm of the mad.