I know that a lease follows the property when it changes ownership, but what if the previous owner's lease says the lease is void upon sale? Is this legal, or do I still need to stick to his terms until their lease expires?
Likely not enforceable. A contractual clause that violates local law is unenforceable and therefor of no effect. Generally residential leases and local laws etc are going to protect the 'unsophisticated' party here which is the tenant. This is true even in a very LL friendly state since it's fairly universally recognized that tenants are generally going to have to accept whatever lease they are given. Hence the 'boundaries' on what a LL can legally do/not do. If this was a commercial lease then the rules may be different since both parties are more sophisticated and likely had more of an opportunity to negotiate the final lease conditions.
Likely not enforceable. A contractual clause that violates local law is unenforceable and therefor of no effect. Generally residential leases and local laws etc are going to protect the 'unsophisticated' party here which is the tenant. This is true even in a very LL friendly state since it's fairly universally recognized that tenants are generally going to have to accept whatever lease they are given. Hence the 'boundaries' on what a LL can legally do/not do. If this was a commercial lease then the rules may be different since both parties are more sophisticated and likely had more of an opportunity to negotiate the final lease conditions.
Yes state law would be important to know here. If you speak to a local real estate attorney they should be able to answer that question briefly enough. Best wishes.