MG/YA fantasy? Son of a single mother finds portal to another world in attic?

[Tahirah]

I read this between 2009-2011. I think their house was also a store that sold antique-y things. The boy (MAY have been a girl idk) lived in the attic. He finds some sort of portal to another world. This guy that only eats fruits comes to live with them. The book was probably middle-grade. SORRY FOR BEING SO VAGUE

[Kris]

Tahirah, what does the boy/girl do in the other world?

Can you describe this world and the challenges it poses?
Is there magic or unusual creatures in this world?

[Tahirah]

I think they are trying to look for something? An old locked box maybe. I cant remember any specifics on the world sorry

[Holly]

Maybe look through this list? https://www.goodreads.com/list/show/8...

[Tab]

100 Cupboards ?

Do you remember the cover?
Part of a series?
Time period /location story takes place?

[Andy]

Makes me think of "Marco's Millions" by William Sleator Marco's Millions or the sequel "The Boxes" The Boxes

Description of "Marco's Millions"

"When Marco's shy and fragile little sister, Lilly, tells him about the strange lights in the basement, he thinks she's imagining things. But Marco is curious, and before long he investigates. He finds a passage into a strange world, where he meets insect-like creatures who seem to know all about Lilly."

Description of "The Boxes"

"Orphan Anne Levi tolerates her distant Aunt Ruth, with whom she lives, but adores her mysterious Uncle Marco, who flits in and out of their lives at irregular intervals. When he gives Anne two unusual boxes with strict instructions not to open them, curiosity gets the better of her. Opening the first one, she releases an unusual crablike creature that grows and reproduces rapidly; the life form and its offspring construct a fantastic palace in the basement and communicate with Anne telepathically. "

[Tahirah]

Its neither of those books :( im pretty sure the cover was dark and mysterious looking, something along the lines of The Twistrose Key or Reckless
Somethings telling me it was set in london but i could be wrong... probably in the 20th century, not exactly mondern day. I think the book contained a map in the beginning too.
The thing i remember most was that an old man who eats fruits comes to stay with them and the mother has to make him fruit salad all the time. Weird, i know

[Rafi]

possibly The Castle in the Attic

[Lobstergirl, au gratin]

Tahirah, are you still looking for this or did you find it?

[Lobstergirl, au gratin]

No response; moving to Abandoned.