What does an owner's representative cost?

Scope. A full mandate across project preparation, design, procurement, construction and close-out sits at the upper end; individual phases sit proportionally below. The AHO booklet no. 9 spreads the fee across five project stages: 19 percent project preparation, 21 percent design, 22 percent construction preparation, 30 percent construction, 8 percent close-out. The largest share falls on construction, because that is where change orders, schedule and quality have to be checked continuously.

Project size. The rate is degressive. Control effort does not grow linearly with construction volume: a residential scheme with 40 units does not need four times as many meetings as one with ten. Small schemes therefore sit at five to seven percent under the 5th-edition table, large ones at around two under the 6th.

Complexity. The AHO booklet no. 9 distinguishes project classes by difficulty; three of five carry table values. A refurbishment under continued operation, a special building with a full permit procedure or a scheme with many stakeholders sits higher than a new build on a clear site.

Duration. Since the sixth edition of May 2025, the table values are for the first time linked to reference values for project duration. If a project drags on, the control effort rises without construction cost rising. That is why percentages alone fall short on long projects.

The table applies to the basic services of project control in project classes II to IV; class II sits roughly a fifth below, class IV about 15 percent above. The project class follows from six assessment areas scored one to five each, client organisation, project structure, stakeholder environment, quality, cost and schedule targets; the average is the class. The bidder scores, the client checks. One of the six areas is the client organisation: a developer with an in-house project department lowers the project class and with it the fee; in class I the fee is calculated by time anyway. Intermediate values are interpolated linearly. Below 15 million euros the table no longer contains values since the sixth edition; there the fee is calculated by time. The 5th-edition table (2020) still ran from 0.5 to 500 million euros and shows how the curve runs below that, zone III in each case: 4.1 to 4.8 percent at 5 million, 4.9 to 5.9 percent at 2 million, 5.6 to 6.7 percent at one million. The 6th-edition values sit in the middle of those ranges.

Project leadership is not included. Where the owner additionally assigns project leadership tasks, the AHO booklet has them remunerated separately by time. The charge rate for a project manager is 18,000 to 23,000 euros per month or 1,000 to 1,300 euros per day, as of the first quarter of 2025. A flat five percent for expenses comes on top. Owner's representation with authority is exactly this combination of control and leadership.

The booklet provides two corrections. For work on existing buildings a surcharge on the basic fee applies, to be agreed in text form; absent an agreement, 20 percent applies where the task is at least of average difficulty. Where a general contractor, general planner or design-and-build contractor is used, the project control fee falls, but only moderately: to 87 to 89 percent of the basic fee with a general contractor or general planner, to 66 percent with a design-and-build contractor after project development. Control does not disappear, it shifts.

For project classes I and V, AHO booklet no. 9 refers to time-based remuneration (section 5); for schemes below 15 million euros the table contains no values, so in practice the fee is calculated under section 5 as well. Two forms are provided: a settlement fee based on hours actually performed and documented, and a fixed fee based on a staffing plan estimated in advance. Under section 4 the fixed fee remains unchanged even if the effort later turns out differently; if the client changes the project requirements, the additional or reduced effort is settled separately.

The section describes the process in four steps:

The charge rates of section 5 para. 2, excluding VAT and expenses; unless agreed otherwise the mid-points apply. They refer to actual deployment time on the project, absences are not charged, and besides staff cost they include the contribution to management, secretariat and office overheads:

This is how it works under the AHO commentary and in practice: the firm sets up a schedule frame with around ten framework activities or milestones, including the project stages with their durations, and enters the staffing per activity by role: leader of project control, project engineer, project assistant. This yields person-months; multiplied by the charge rates, it produces the fixed fee per project stage. For comparability the fixed fee is usually also stated as a percentage of construction cost; so project control for schemes between 5 and 15 million euros lands at four to six percent under the 5th-edition table and in our experience, smaller schemes above that; project leadership comes on top. A flat five percent for expenses comes on top. Defined single tasks, such as the review of a general contractor agreement, are charged by time with a budget cap. An instalment plan is agreed (section 8), in practice along the project stages; if the duration extends beyond what was agreed, an adjustment is to be examined (section 4 para. 8).

A staffing plan for a residential scheme with 8 million euros of construction cost and 24 months' duration could look like this, using the mid-points of the AHO rates:

This is a model calculation with disclosed assumptions, not an offer. It shows why percentages rise on smaller schemes: the minimum staffing of a project does not fall in step with construction cost. Whether owner's representation with authority is included decides the share of project management, and with it the largest item.

The AHO booklet calculates its own standard example both ways, a research building with roughly 143.7 million euros of eligible cost and 55 months' duration: 154 person-months yield 2,442,500 euros net, the fee table 2,856,297 euros. Both routes sit at 1.7 to 2.0 percent of eligible cost; the difference is the room for negotiation (chapters 7.1.3 and 7.2).

What matters is not the rate but what it prevents. Four levers, each on its own in the order of the fee or above:

Award prices. In our experience a general contractor usually comes in 10 to 15 percent above the sum of separate awards; the premium depends on market conditions and contract maturity and shows reliably only in comparison with the individual bids. Whoever awards separately with control, or has the GC contract reviewed before signature, starts here. We set out the comparison in General contractor or separate trades?

Change orders. A change order is to be examined on merit and amount. Without review it is paid; with review it is negotiated, reduced or rejected. Where the cost arises is shown by a Hertie School study (Kostka and Anzinger, 2015): 119 completed large German projects ended on average 73 percent above the original estimate, with design deficits and lack of control as the main causes. Large public projects cannot be transferred to a private scheme; the direction still holds.

Construction period. Every month of delay costs interim financing, lost rent or a postponed sale, and site overheads. Schedule control is the service that is least visible and saves the most.

Defects. A defect noticed before acceptance is the contractor's problem. One noticed afterwards is a dispute with an open outcome. Preparing acceptance and pursuing defects is therefore no formality but the last place where the fee is earned.

Assume a residential scheme with 8 million euros of eligible construction cost and a full mandate of project control and project leadership at five percent: a fee of 400,000 euros over the whole duration. Counter-calculation: a single avoided or reduced change order of five percent of construction cost covers the fee in full. A general contractor premium of ten percent, avoided in whole or in part by separate awards with control, would equal 800,000 euros. One month less construction time equals, at this volume, a five-figure sum in financing and site overhead costs.

This is a model calculation with the ranges given above, not a project result. It shows the ratio, not the outcome: a fee in the single-digit percent range competes against items that are individually larger than the fee itself. As a rule, professional control therefore pays for itself. Whether it does for a specific scheme can be estimated before appointment, and it should be.

We disclose the ratio of fee to leverage before appointment, and we say so when it does not hold for a scheme. We regularly act as owner ourselves, with our own capital at risk, and therefore know what a change order costs that nobody has examined.

As owner's representation in Munich and Bavaria we offer full mandates, individual phases and single tasks such as the review of a general contractor agreement. What the role covers in detail is set out in What does an owner's representative do?