Helena spent her childhood in Wayne Manor, which is big and luxurious and totally amazing. She lived there until she was in her late teens when she went to university. Following the death of her mother, she became uncomfortable living in the house alone with her father and moved into a swanky penthouse in a posh part of Gotham. This was her home for basically all of her canon, except for a brief, misguided stay in California. Eventually she moved back to the penthouse. Also she owns Wayne Manor, but it sits empty most of the time. Sometimes Dick stays there. It's like... a guest home.

She hasn't spent any significant time in the MAC. She stayed briefly in an upscale hotel before moving into Charlie's apartment, taking over the room of the previous Helena. I'm pretty sure Barbara and Stephanie live there now also? Living with other people has been a bit trying for her. Hel keeps to herself most of the time. She spends most of her time at home in her bedroom, the bathroom or in the kitchen. It isn't an easy situation for her, but she agreed to look after the place and Charlie for Dick.

She's pretty spoiled when it comes to housing. Her standards are incredibly high and she realizes this. She was raised in the lap of luxury and has no need to experience anything less, so why should she? Upscale amenities are important to her, like marble sinks, upgraded kitchens, etc. She loves taking long baths, so an updated bathroom is a nonnegotiable with her. She wants the best, and since she can afford it, she sees no reason not to have it.