Inexpensive Commercial Real Estate Lease

Looking to find a space in Katy, Tx for a commercial real estate lease for under $500/mo, preferably under $300/mo. It can be a closet for my personal needs – I just need to be able to receive mail there, and no a PO Box won’t do. If anyone knows a good commercial real estate agent or knows of a place that fits this criteria, it would be greatly appreciated.

Thanks, Reddit!