It appears that you have a month-to-month tenancy and that the landlord can, indeed, raise the rent with 30 days' notice.
This is more a matter of negotiating leverage (a business issue) than legal rights. It might be helpful for you to discuss this matter - including relevant market conditions - with a lawyer who, then, can negotiate on your behalf.
This information does not constitute legal advice and does not establish an attorney-client relationship.
I agree with Mr. Shultz: it appears that you are in a month-to-month lease with your landlord. In such case, he is free to raise the rent on 30 days advance notice.
Generally, with commercial leases, the rights of each party are freely negotiable and are a matter of contract. So unless the lease you signed has specific language prohibiting the landlord from raising the rent, he may unfortunately do so.
The information presented here is general in nature and is not intended, and should not be construed, as legal advice for a particular case. This posting does not create any attorney-client relationship with the author, and Pham Law Group does not represent you as your attorneys until retained by a written retainer agreement signed by both parties.
I agree with previous attorneys. Your landlord is free to raise the rent absent a fixed term lease. If he has increased the rent during lease period, then it would not be legal. He has the right to determine lease period.
DISCLAIMER—This answer is for informational purposes only. It doesn't constitute legal advice. This answer doesn't create attorney client relationship.