Build vs buy lease administration software for critical dates and notices

Should you build your own critical date tracking or buy lease administration software? If you hold more than a handful of leases with options, buy the date engine and put your own effort into how your company decides: which deadlines go to the real estate committee, who reviews first, when the site review starts. A date in a spreadsheet costs nothing. The expensive part is turning clause language into the correct notice window, keeping it correct after every amendment, and making sure the right person sends the right notice the right way.

Critical lease dates are the deadlines a lease creates: rent commencement, expiration, renewal and termination option windows, co-tenancy cure periods, kick-out rights, and notice deadlines tied to each. Exercise a renewal option on time and you keep its protected terms; let it lapse and you negotiate from weakness or sit in holdover. Catch a termination window and you can exit a site you meant to leave, instead of carrying it for another term.

This piece is part of our series on build vs buy AI agents for corporate real estate.

What does "build" look like for critical date tracking?#

Build usually means one of two setups. The first is a spreadsheet of expiration and option dates, with calendar reminders set in Outlook or a shared team calendar. The second is date fields inside an IWMS or lease administration system, populated by hand during abstraction and maintained by the lease team. Both work when someone reads every lease carefully, enters the right date, and updates it whenever anything changes. That last condition is the one that erodes.

Here is what a date tracker has to handle to be trusted across a portfolio:

Why do spreadsheet reminders miss notice windows?#

Spreadsheet reminders miss notice windows because they store an outcome rather than the rule that produced it. A cell that says "notice due 3/14/2027" is correct only as long as the expiration date, the clause wording and every later amendment agree with it. When a lease is extended, relocated or assigned, the reminder does not know. When a clause says notice must arrive no earlier than twelve months and no later than nine months before expiration, a single reminder date cannot represent the window. When the right depends on the tenant not being in default, the reminder fires regardless.

Public data on missed critical dates in private portfolios is thin, so a federal example is a useful analogy rather than a benchmark. A 2020 audit by the GSA Office of Inspector General found that as of September 2019, 1,022 of the 8,184 active leases it reviewed (12.5%) were in extension and 68 were in holdover. In a tested sample, the agency missed required milestones on 12 of 16 leases (75 percent). Corporate portfolios run differently, but the mechanism is the same: the dates were known, and the process around them needed to hold.

When does building your own date tracking make sense?#

Building is a reasonable choice in a few cases:

• Small portfolio, simple leases. A few dozen leases with plain expiration dates and few options can be tracked in a controlled spreadsheet with a named owner and a backup.
• An IWMS that is already well maintained. If your team abstracts every amendment within days and audits date fields each quarter, adding reminders to what you have may be enough.
• Short remaining horizon. If most leases expire within two years and you are not renewing, the value of a new system is limited.

Outside those cases, homegrown tracking tends to work until the person who built it moves on, and the cost of keeping it current sits after launch. We work through that cost in what it costs to build and run your own AI for real estate operations.

The third path: buy the date engine, run your own review routing#

The third path is to buy the date engine and notice drafting, then run the parts that reflect how your company decides on top. Which deadlines need a real estate committee review? Which go to the regional director first? How many days before a window opens should a site-level performance review start? Those are policy choices, and they differ by company.

Ask every vendor who builds that routing. Some expect your team to configure or code it on their platform. With REAL, you define the policy and REAL's engineers build and maintain each workflow on the shared record, through custom workflows. One example: every renewal option within 180 days is routed to a renew, renegotiate or relocate review with the store's occupancy cost attached. For the decision itself, see renewal vs relocation.

What REAL does here#

REAL's critical dates agent tracks options, renewals, terminations, rent commencements and co-tenancy notice windows across the portfolio and calculates each window from the clause language. Judged on the standard that matters:

• Action: it drafts the notice letter pre-filled with the party, clause and delivery method, for a person to approve and send.
• Evidence: each date links to the source clause, and an amendment re-baselines the dates automatically.
• Outcome and coverage: every option across the portfolio carries its financial impact, so the team prioritizes by value, and the same record feeds lease accounting, so an exercised option reaches the ASC 842 schedule without a second handoff.

Initial agents go live in two weeks, running in parallel with your current process first. Dates are only as good as the abstraction behind them; see build vs buy for AI lease abstraction.

Build vs buy scorecard for critical date tracking#

Questions to ask before you decide#

1. 01How many renewal, termination and co-tenancy rights sit in our portfolio today, and how many are within 18 months?
2. 02For each one, can we show the clause, both ends of the window and the delivery method?
3. 03How many amendments did we sign last year, and how long until each reached the date tracker?
4. 04Who receives each reminder, and who backs them up?
5. 05Where is proof that last year's notices were sent and received?
6. 06Who builds and maintains our review routing, and how does it change when our policy does?

The expensive lease mistakes are rarely the ones negotiated at the table. They are the dates nobody recalculated after the last amendment. For a structured starting point, REAL publishes a critical dates resource, and a portfolio-wide check of what your system says against what your leases say is covered in the lease-to-system audit.