But I do have a 3 strike policy on smoking inside and the third time someone is caught smoking inside or with smoking paraphernalia inside they get evicted.

I heard of one investor who went through some hoarders boxes and end up selling items on ebay - 103k worth of collectible toys/comics/disney paraphernalia and a couple months of work.

“Drug-related illegal activity” means the illegal manufacture, sale, distribution, purchase, USE, or possession with intent to manufacture, sell distribute, or USE of a controlled substance (as defined in Section 102 or the Controlled Substance Act (21 U.S.C. 8002) or possession of drug paraphernalia.2.Resident, any member of the resident’s household or guest or other person under the resident’s control shall not engage in any act intended to facilitate illegal activity, including drug-related illegal activity, on or near the said premises.3.Resident or members of the household will not permit the dwelling to be used for, or to facilitate illegal activity, including drug-related illegal activity, regardless of whether the individual engaging in such activity is a member of the household.4.Resident or members of the household will not engage in the manufacture, sale or distribution of illegal drugs at any locations, whether on or near the dwelling unit premises, or otherwise.5.Resident, any members of the resident’s household, or a guest or other person under the resident’s control shall not engage in acts of violence, or threats of violence, including but not limited to the unlawful discharge of firearms, prostitution, criminal street gang activity, intimidation, or any other breach of the housing agreement that the other wise jeopardizes the health safety or welfare of the landlord, his agents, or tenants.6.VIOLATION OF THE ABOVE PROVISIONS SHALL BE A MATERIAL VIOLATION OF THE HOUSING AGREEMENT AND GOOD CAUSE FOR TEMINATION OF TENANCY.

Could the drug paraphernalia cause her to lose the voucher?

What you are looking for is drug paraphernalia  in plain sight. 

Besides leaving evidence of manufacturing and paraphernalia (like bent spoons, snapped rubber bands, used needles, burnt Tupperware with white powdered residue, empty spray paint cans) They also literally left actual drugs everywhere.

"Drug-related illegal activity" means the illegal manufacture, sale, distribution, purchase, use or possession with intent to manufacture, sell, distribute, or use of a controlled substance (as defined in Section 102 or the Controlled Substance Act [21 U.S.C. 802]) or possession of drug paraphernalia. b.

Buried under piles of snow, which thawed weeks after I moved in, was a keg (1/2 full), broken drug paraphernalia, broken beer bottles, cans strewn across the lawn, and the biggie -- somewhere around 100+ pounds of dog poo, which emerged little by little as the thaw came.It was a NIGHTMARE!

Sometimes possessing larger quantities and other paraphernalia (scales, baggies, etc.) is enough to get intent to distribute charges which is a felony.

1., Do a surprise  legal check on the unit ,if there is drug paraphernalia take pictures and  issue a lease violation. 2.