Does not accepting a gift make you ungrateful?

Okay a little backstory: my husband and I are moving home next year and look to settle and buy a house. Well my MIL offered to buy us this gutted house next door to them and remodel it. As grateful i am for her wanting to help like that I just wouldn’t feel right accepting something like that and it’s also just not the area we want to live in. My husband is also expressing concern that we’d kind of have that constant feeling of it’s not actually our home and i do agree. But now to some family and friends we’re looked at as ungrateful for the fact that we rejected their offers even after they were ready to buy and start remodeling next month. So the question is it truly always ungrateful to deny a gift no matter what kind?