The single most foundational field in a lease abstract is the lease structure, because it determines who pays operating expenses and therefore what the tenant's true occupancy cost is. Getting the structure right is the prerequisite for interpreting every other operating-expense term in the lease.
Triple Net (NNN)
In a triple net lease, the tenant pays base rent plus a proportionate share of operating expenses — property taxes, insurance, and CAM — on top. The base rent looks low, but the true cost is base rent plus the pass-throughs, and CAM alone can add 30 to 60% to the base. For NNN leases, the abstract must identify exactly which operating expenses pass through, because that list defines the tenant's real obligation.
Gross and Modified Gross
In a full gross lease, the landlord pays operating expenses out of the base rent — the tenant's cost is more predictable. Modified gross sits between NNN and gross: the tenant pays base rent plus some specified expenses but not others, with the split defined in the lease. The abstract has to capture exactly which expenses the tenant carries under a modified gross structure.
Base Year Leases
In a base year lease, the tenant pays its share of operating expenses only above a base year amount. The abstract must identify the base year and what's included in it, because the base year sets the threshold above which the tenant starts paying — a high base year protects the tenant, a low one exposes them. The AI agent identifies the structure and extracts the corresponding expense terms for each type. It's demonstrated at omnionlinestrategies.com/ai-agent-cre-lease-abstraction.