Small landlords need to know the difference between a tenant working from home and a tenant turning the rental into a business location.
A laptop job is usually not the problem. The risk starts when the business brings in customers, employees, pets, food prep, chemicals, extra water use, noise, odors, parking issues, or liability exposure.
Examples include haircuts, dog grooming, nail or lash services, cosmetics, catering, baking, daycare, repair work, or product storage.

Small landlords should be careful about:
Lease language: Require written permission before any business use.
Insurance: Your landlord policy may not cover business-related injuries or damage.
Zoning/code issues: Residential properties are not automatically approved for commercial activity.
Property wear: Extra water, grease, chemicals, pets, trash, or foot traffic can damage the unit.
Liability: If a customer, client, or animal is injured at the property, the landlord may get pulled into the problem.
Bottom line: The issue is not the tenant earning money. The issue is whether the rental is being used in a way that creates risk you did not agree to, insure, or price into the lease.