What you're looking at is usually called a double net lease, or NN. The tenant reimburses the three nets, meaning property taxes, building insurance and ordinary maintenance, and the landlord keeps roof, structure and often the parking lot. Strictly, triple net means only that those three cost categories move to the tenant. It says nothing about who replaces a failed roof membrane or repaves a lot, and plenty of leases that hand back the structure still get marketed as NNN because the phrase sells.
The version with nothing left for the owner is normally called absolute net, or bondable. There the tenant carries roof, structure, casualty and condemnation risk too, and keeps paying rent even if the building burns. Those exist, and they're common with the strongest corporate tenants, and they price at lower cap rates precisely because there's less for you to do.
So the label on the flyer tells you very little, and the lease tells you everything. Read the maintenance and repair section, the casualty section and the definition of capital repairs before you look at the cap rate.
One more thing that catches new net-lease buyers. Even when the tenant carries the property insurance, you'll normally want your own liability policy behind theirs and you'll want to be named as additional insured on their policy, with the certificate in hand at closing. Tenant insurance protects the tenant's obligations. It's not a substitute for your own coverage on the entity that owns the building.
