From 20 offers to one decision

This site grew out of a real project: a 1972 house, ~160 m², two residential units, an old oil boiler — and the wish to do it right. Here's the honest path from many offers to one decision.

The starting point

Around 20 vendors contacted, for PV and heat pump. It quickly became clear you can't just lay the offers side by side. Each contained different things, in different structures, with different options. So the first real work wasn't "comparing" but making them comparable.

How the field narrowed

From the long list, a few candidates crystallised by normalising every offer to the same scope (see "Comparing offers honestly"). Then the real differences emerged:

• Who installs a new meter cabinet, who only modernises? (Up to ~€4,000 difference.)
• Are roof tiles, backup, the wallbox device included or options?
• Which inverter platform — and thus: how well can the system be controlled locally?

The central trade-off

It came down to a fundamental question: the cheapest one-contract package (often with a closed, cloud-bound heat pump) versus the slightly pricier split that allows genuine local control of PV and heat pump. For the priority "independence/local control," the split won on the criterion that mattered most.

What carried the decision

Not the lowest price, but the effective cost at equal scope plus the soft but important factors: local controllability, serious service, complete scope, manageable risk. A canonical comparison worksheet (a tab per vendor, a shortlist tab with identical criteria) kept it all traceable.

What you can take from it

• Get more offers than feels "necessary" — the spread is large.
• Normalise the scope before comparing prices.
• Define your priorities in advance (next chapter) — otherwise the brochure decides for you.
• Keep everything in one document; memory deceives.

In short: ~20 offers became one choice by bringing everything to equal scope, comparing effective cost, and measuring against clear priorities (above all local control). The lowest price was not the yardstick.

Next: my priorities — and why local control came first.