so i have a question is it legal for me to rent out lots that allow pets then lots that dont allow pets in the same park ?
No because that means you’re discriminating against some of the tenants. You should follow your insurance company’s guidelines and be diligent about enforcing it consistently.
If you let one tenant have a pit bull but another cannot then how do you explain that to the FHA?
One property, one policy otherwise it is discrimination.
If you took over ownership of the park and new policy says no dogs over 30# and current tenants have larger dogs would you make them move or get rid of their dog?
Changing rules mid stream generally involves grandfathering other than in the case of dangerous breeds… It is best to make strict rules to control pet owners rather than trying to control the pets. If owners do not follow the rules and keep their pets under control you can then get rid of the pets or the tenants.