I'm going to be starting my mod that has an arena and large mansion that doubles as another playable guild. I want to keep it lore friendly so,

I need a rich family or someone who could fund an extremely expensive and expansive area. Also, suggestions would be nice to where I should place this compound on skyrim. Or any general feedback.

I know that no one may fit the bill specifically, but i'm sure there is someone or something fun I can use so that a large compound seems feasible. Thanks fellas!

Well Maven Black-Briar is quite wealthy. I could see her funding an arena, the Briar mead would flow like water and she'd make a killing off her cut of the gambling profits that I have no doubt she would take.

As for a location of the arena...I would suggest Whiterun Hold. The western section of the hold that leads to the Reach has plenty of flat land to build an arena. Plus it would put it in a some what centralized location.

Any of the Jarls family members could sponser this. Also the Battle-borns or Grey-manes could afford it. The Silverhands from Markath are another option. Only problem you'll have is making sure who you choose will survive the civilwar no matter who the victor is.