This is a challenge that I remember from when The Sims 2 Exchange was function, and since it's defunct now there's the issue of not being able to get the house but I'm also going to remake the house to the best of my abilities. The challenge was originally created by PollyG on TwinkiesSims and on The Exchange.

About the house: I have a good frame of reference for most of it, the only thing is just going to be the painting, I wouldn't bother trying to click the link. Since the exchange is now defunct. Certain things are going to be missing from the new copy such as the portrait of your Great Aunt and the newspaper, but I've replaced it with a copy of the same size, just of a different thing. You start out with less than $100 either way. Also you can expand a little bit if I remember the rules from the original correctly

It's a shame about your dear old aunt, but you really lucked out. She left you the cottage and $50,000 to fix it up a little. She also left you some of her cherished family heirlooms - one in each room, including the family tree outside.

Rules
Get the cottage here. Heirloom Challenge

Move in a sim.

Give 'em their $50,000 inheritance (a motherlode).

Do your best to make a nice home using anything you've got. You may add structures if your sim can afford it.

You may re-design any object in the house, but you may not sell it. Dear old auntie will be watching!

Thank you for posting this! I still have the Heirloom lot in my game, but sort of forgot all about it!

After you build the house, with your motherlode, and you keep everything Auntie gave you, then what? What, exactly, is the challenge? Is the old stuff ugly, and you have to decorate around it, to keep it visible, but less tacky-looking?

Michelle, ephemeraltoast's Heirloom Challenge is archived on Hoopty's storyreader, if you want to check it out:
Toast's Heirloom Challenge

Thanks, Lorinsv! That really does turn into a lovely house, with the right building and decoration. Also, it really makes it clear what kind of a challenge this is. It's a building challenge, not a play challenge.

It looks fun!

I remember this challenge. I wanted to do it in Silver Bend, but thought it was long gone.

Well, you could try a similar one with the Messy Messlot challenge. The lot is available for download from Modthesims, and I suppose there's got to be a few items you could designate as heirlooms.

Or, move in some poor sim long enough to create/buy a few heirlooms, then kill them off (because if you just move them out, all the furniture goes away, but you can get around this by placing them in University, and playing them through, if you don't mind). Then use that for your dilapidated/heirloom lot, and see what you can make out of that.

It's a cool building challenge, I think, to take something bland and ill-designed and make it beautiful and livable.

You know, a lot of the Maxis-designed lots that come in the lot catalog are ill-designed and bland. Why not use one of them? In fact, you could just buy your own "heirlooms" when you move in, before you mother-lode.