Boundaries with in laws?

How do you set appropriate boundaries with your in laws in terms of seeing you/your child? My in laws have been a problem since the start-and before I came into the picture. Extremely controlling, narcissistic, over bearing. My husband is their only child-and I try to give him grace because they constantly fight any time he tries setting a boundary-but it’s to the point I worry when our kid is born, they will continue to be controlling and over share their opinion on how I parent, as they do with everything else. They are really excited to be grandparents, so I don’t want to rob them of that or rob my child of seeing their grandparents, but any advice on how to set a happy medium balance where I don’t feel constantly exhausted and ran over by them, while still not being the monster who doesn’t let their kid see their grandparents? My husband agrees with me and tries his best, but genuinely struggles because his parents simply don’t respect what he has to say. I don’t feel it’s my place to say “you need to stop talking to your parents”, but they have become that suffocating. Just want to figure this out before baby gets here. Any advice is helpful!