Moving parents in with us

I think you would need to buy a property with a flat or bungalow attached where they could still live independently. You shouldn’t cut off any help they already get. I don’t like to mention it, but we are all getting older. You don’t know how long you would have to look after them nor do you know how long you would be able to look after them. Elderly people don’t always cope with moving house / district. It might be better to explore what other help they need that can be provided where they are.

After my MIL died, we did consider selling FIL's home and buying a larger house, so that he could live with us, and our two children. This became an issue when inheritance was mentioned, and the other two siblings would be wanting their share. We would have had to sell to find the money. It never got nasty, just involved.
So it never happened. Turned out OK in the end, as FIL's older grandchildren took it in turn to live with him. They had a safe place to live while saving for their own places and FIL had company with people he loved.

If they were elderly I would certainly do it. Perhaps if your DH isn’t able to be present and support them with what they need, I would get him to hire a helper/carer though and not rely on me.

Please consider how you would feel if your husband pre deceased his parents after they moved in to live with you. Could you cope with your own loss and theirs? I only mention it because it happened to a friend of mine. Her in laws made her life a misery after her husband died suddenly and eventually she had to 'evict' them.