Grandma passed 2 yr ago. she owned the modular in park it passed to my dad. does the lease follow if there was one? what can we do if there wasn't one

Grandma passed 2 yr ago. she owned a modular in park, it passed to my dad. The Park is continuing to raise the rent. Which I know they can. The park continues to deny people from getting in the house, Which again I know they can. But I was trying to sell it through a realtor. The park said they have the first right to buy and I need to pay for an inspection before I can sell per the lease agreement (which they refuse to provide). They had made an offer when Grandma was alive and trying to sell it and she declined. I understand it switched hands so the rule can apply again. But does it in this case? No one signed a lease when she passed or when it got out of probate. Do those rules still apply to him? If so how is it possible for it to only work in their favor, Why should he follow the lease agreement when it isn't in his name? Again this is based on a lease that my grandmother supposedly signed that they will not provide a copy of.