Tenant asks if she can smoke weed and have a gun on the property

[Jose Petitfrere]

At the moment, im currently accepting a Sec. 8 tenant with good credit and no criminal history. I have thoroughly screened the tenant and spoken with the tenant's previous landlord, employer, and references, and they had no issue with paying rent on time and no issues with neighbors. The tenant works as a security officer and uses the gun for work. The tenant has also shown proof of a firearm license and a medical marijuana card. It is to my best understanding, as a landlord and RE agent, that I cannot discriminate against marijuana for medical use because of Fair housing laws. The tenant has asked if she can smoke at the unit and has a gun for her job as a security officer. As a landlord, I don't mind if the tenant smokes as long as it's not inside the unit. As for the gun Im not sure the neighborhood where the property is located doesn't have the best reputation, and having a gun is a good defense; note the property also has a 24/7 security system in place, and the tenant uses the gun for her job. But having a gun can also be a huge liability. For landlords who have had a similar situation, how did or would you handle this?