Reconciling two renovation quotes for a 45 m² serviced apartment in Zurich

[planTheSignal]

Choosing the lower quote and simply adding a large contingency are both plausible approaches, but I do not trust either while the scopes remain inconsistent. This is a 45 m² serviced apartment in Zurich with a preliminary budget of CHF 203,200, yet two contractors have produced very different totals for what was presented as the same renovation.

The work includes a kitchen, bathrooms, floors, painting, checks to the electrical installation and some energy improvements; there is no planned extension. My main concern is whether items such as opening walls, accessing plumbing and reinstating finishes have been included. One vague electrical allowance could mean inspection only, while another contractor may have assumed replacement work.

Would you first require both firms to price an identical schedule showing exclusions, concealed-service assumptions and permit timing? I would still retain a contingency, but only after those points explain as much of the gap as possible.

 

[otis.cove]

Before choosing a contingency percentage, make both contractors reprice against the same written schedule. Ask each to separate demolition, disposal, plumbing, electrical work, making good, materials and any permit-related allowance. Also ask what happens if concealed services cannot be reused.

Is the apartment currently operating, and can noisy or water-off work happen without restrictions? Sequencing costs can differ sharply if access is limited.

 

[planTheSignal]

It is currently operated as serviced accommodation, although I can take it out of use for the renovation. Access is therefore less of a concern than the length and reliability of the programme. Neither quote clearly explains plumbing access or what “electrical checks” include. One also treats making good after opening walls as an extra, which may account for part of the gap.

 

[patient_sparrow]

That making-good exclusion is significant in a small apartment because opening even a limited route can affect several finished surfaces. I would request a marked-up plan showing where the contractor expects to open floors, walls or ceilings for plumbing and cables. Without that, the flooring and painting figures may look complete while depending on optimistic assumptions.

 

[timo_taxes]

I would not automatically add a large blanket contingency to an unclear quote. That risks accepting ambiguity twice: once in the contractor’s price and again in your reserve. First reduce the unknowns with targeted opening-up where permitted, moisture readings around wet areas, and confirmation of accessible service routes. Then keep the contingency under your control rather than embedding it in the contract sum.

 

[nimble_creek]

There is a counterpoint: investigation itself cannot reveal everything, and opening occupied building fabric may be restricted or create repair work before the project starts. Ask both contractors to list unit rates or an agreed method for valuing concealed-condition changes. The contractual process for discoveries can matter as much as the reserve amount.

 

[otis.cove]

Also pin down “moderate energy upgrades.” That phrase could cover very different work and dependencies. Which exact elements are included, who confirms compatibility with the existing building systems, and does any item affect approvals or the programme? I would place uncertain energy items and long-lead materials on a separate decision list rather than letting them blur the base renovation comparison.

 

[otis.cove]

For sequencing, ask for a simple programme showing demolition, investigation, service alterations, inspections or approvals if needed, waterproofing, finishes and commissioning. Then ask which materials must be ordered before demolition and which can wait until dimensions are verified. A quote with a credible sequence and named assumptions may be safer than the cheaper one, even before contingency is considered.

 

[ari.brooks]

Do not overlook moisture just because there is no structural extension. Wet-area damage can turn a finishes project into substrate and drying work. The useful questions are whether the price includes removal back to sound material, drying time, retesting, waterproofing preparation and reinstatement. If those are exclusions, the programme should show where time is reserved for them.

 

[LuckyMoss]

I’d turn this into three documents before deciding: one common scope and finish schedule, one exclusions/assumptions table completed by both bidders, and one risk list assigning each unknown to either contractor pricing or the client contingency. Include plumbing access, electrical remedial work, moisture, wall and floor repairs, material lead times, and permit timing. Once the bids are normalised that way, the appropriate contingency should be much easier to judge.