The useful competitor set is the collection of spaces that could serve the same tenant. Define those spaces, separate known availability from unknown inventory and compare their full quoted lease cost. A building count and a market-wide vacancy rate can both miss the decision in front of you.
Check what the headline market statistic actually measures
CBRE’s March 2026 shallow-bay research defines its segment as buildings under 50,000 square feet with clear heights between 14 and 28 feet. It reports that shallow-bay vacancy was 2.5 percentage points below overall industrial vacancy by early 2024. That is dated segment-level evidence, not a vacancy estimate for your local 1,000-square-foot suites.
A 40,000-square-foot property might contain suitable small spaces, one large occupier or an arrangement that cannot meet the target tenant’s requirements. Define the size, access, clear height, office proportion and other features that matter to the proposed product. A label such as flex or micro-bay does not settle those details.
Source: CBRE, 24 March 2026: shallow-bay segment definition and historical vacancy comparison
Connect each suite to one building
Keep a building table and a suite table joined by a stable property identifier. Building records hold the address, total area and property-level evidence. Suite records hold usable area, dimensions, features, asking terms and dated availability. One source may be current on ownership while another is current on a vacant suite.
Deduplicate repeated advertisements before counting availability. Record observed vacant space, advertised space with unconfirmed possession dates and unknown occupancy separately. A listing can be pre-leased, stale or offering space that is still occupied. Availability and physical vacancy are different measurements.
If there is no complete denominator of comparable suites, show a count of known matching offers. Dividing listings by an incomplete inventory produces a percentage with a misleading appearance of precision.
Make missing inventory part of the conclusion
Fictional research case: 36 verified suites meet the target criteria and three are advertised available at the observation date. Another 20 potential suites have unresolved sizes or configurations. The observed advertised-availability share is 3 ÷ 36 = 8.33% within the verified subset only.
The extreme bounds below assume all twenty unresolved records turn out to be relevant suites. They are not plausible market forecasts. Their purpose is to show how little the verified subset alone can establish when the missing records could materially change the answer.
| Case | Relevant suites | Advertised available | Share |
|---|---|---|---|
| Verified subset only | 36 | 3 | 8.33% |
| All 20 unknowns relevant; none advertised | 56 | 3 | 5.36% |
| All 20 unknowns relevant and advertised | 56 | 23 | 41.07% |
Choose the next research task by its effect on the decision
Do not fill missing records in alphabetical order. Start with the properties nearest the proposed site, the largest clusters of potentially relevant suites and the records most likely to change the competitor set. Keep a reason for each priority so the review queue is explainable.
After verification, update both the denominator and the count of advertised spaces. Retain the prior observation rather than silently overwriting it. A falling listing count could reflect leasing, withdrawal, source failure or a classification change. A dated change log helps distinguish those explanations.
If a building cannot be classified, leave it unresolved. The investor can decide whether the remaining uncertainty is acceptable for an initial screen or requires more fieldwork. The data should not make that judgement invisibly.
Compare the cost of the space the tenant would actually take
A lower asking rate per square foot can still produce a higher monthly cost because the suite is larger or pass-through expenses differ. Put annual and monthly rates on the same basis and state which expenses are included. Read the actual quote or lease terms; a label alone is insufficient.
In this fictional comparison, A and B quote annual base rent plus estimated annual property-expense pass-throughs. C’s assumed gross quote includes those same property expenses. All three exclude utilities, tenant-specific services, alterations, deposits and incentives. The numbers are not market observations.
| Suite | Area | Annual base rate / sq ft | Property expenses / sq ft | Comparable monthly cost |
|---|---|---|---|---|
| A | 1,000 sq ft | $18 | $5 estimated | $1,916.67 |
| B | 1,200 sq ft | $16 | $7 estimated | $2,300.00 |
| C | 1,000 sq ft | $21 | Included in assumed quote | $1,750.00 |
Test costs and fit together
For A, the calculation is 1,000 × ($18 + $5) ÷ 12 = $1,916.67 per month. B has the lowest base rate but the highest cost for the whole suite. C has the highest base rate and the lowest cost on the deliberately matched expense assumptions. Confirm those assumptions before treating a gross and a net quote as comparable.
If estimated property expenses rise by $2 per square foot annually, A adds $166.67 per month and B adds $200. The treatment of C depends on its actual lease, including any expense stops or later increases. Do not assume a gross label fixes every future charge.
Then apply the physical screen. A cheap unit that cannot accommodate the intended use is not an equivalent substitute. Conversely, do not discard a larger space just because it falls outside a preferred band if it could realistically serve the same tenant at a similar total cost. Keep strict matches and plausible substitutes in separate groups, with the inclusion rules stated.
Implement the analysis in five steps
A compact working file can have four tabs: buildings, suites, comparable lease costs and unresolved records. The output is a decision about the next research or underwriting step, with a clear view of the gaps.
- Define the target tenant requirements, size range and research boundary. Identify required features separately from preferences.
- Create a building-to-suite inventory. Preserve sources and dates and remove repeated advertisements for the same space.
- Separate confirmed fit, plausible substitutes and unresolved records. Calculate availability only for a clearly defined denominator.
- Translate asking terms into a comparable monthly cost and test uncertain expense inputs. Keep physical fit visible beside the cost comparison.
- Verify the gaps most likely to change the conclusion, then record what the evidence supports and what would justify updating the model.
The value is in maintaining a defensible comparison
The hard part is often the connection between messy source records and a consistent question: which spaces compete with ours, on what terms, and as of when? A repeatable system should preserve those definitions, surface changes and route uncertainty to a reviewer. That is the work worth discussing once the first comparison is useful.
Sources and further reading
Sources checked 12 October 2026. Examples and workflow suggestions are Dart editorial guidance.
Build around the suite your team is targeting
Bring your target suite range, research boundary and a few known competing buildings. Dart can help scope a maintained building-to-suite inventory, comparable lease-cost analysis and a focused verification queue.
Talk to Dart ↗Explore the related Dart work