What a day rate that is too low is hiding

You receive five proposals. Day rates range from €180 to €480 for an identical job title. The temptation is to conclude that some are too expensive. The reality is that the five are not selling the same thing, and that the lowest rate simply moves the cost somewhere else.

Where the difference goes

Actual seniority. A "senior developer" job title means nothing without a definition. Ask for years of professional experience, not years "using the language", and insist on meeting the person before signature. A two-year profile billed as senior is the most common mechanism behind a low rate.

Turnover. At a low rate the provider cannot retain people. A replacement mid-assignment costs you between three and six weeks of ramp-up, which you pay at the same rate. Two replacements over a one-year assignment cancel the entire apparent saving.

Steering load. A low-cost provider often delivers with no internal code review, no documentation and no product owner on their side. Those tasks do not disappear: they land on your team. An internal engineer at €600 a day spending two hours a day reviewing external code costs €150 per day per supervised profile. The comparison changes.

Compliance. Producing a compliant DPA, completing a security questionnaire, maintaining an access register: that requires a dedicated person. The structures with the lowest rates do not have one, and you find out when your DPO blocks the contract.

The calculation to make

Compare on the full cost of a deliverable, not on the day rate. The most useful formula is:

Real cost = (day rate × billed days) + (internal supervision cost) + (replacement cost) + (cost of any delay)

On a one-year assignment with two profiles, a 30% rate gap disappears entirely as soon as one replacement occurs and two hours of daily internal supervision are needed.

What a high rate does not guarantee

Symmetrically, a high rate proves nothing. A Paris firm at €750 a day can assign you a junior profile supervised remotely, and the cost structure justifying its rate — offices, sales force, group margin — brings you nothing.

The rate is only a useful indicator when set against written commitments.

The five questions that actually discriminate

1. How many people will be trained on our file, by name?
2. What is the contractual replacement time for a profile who is not right, and who pays for the replacement's ramp-up days?
3. Who performs code review before we see the work?
4. Can you provide a DPA and a completed security questionnaire before the first technical meeting?
5. What exactly does your weekly reporting contain? Show one, anonymised.

The answers to those five questions explain the rate gap far better than the rate itself. A provider who answers all five precisely and charges 30% more than one who holds none of them is, on full cost, the cheaper of the two.