The honest answer is: it depends on what the site has to do. But "it depends" doesn't help you decide, so here are concrete references.
How much does a landing page cost?
A high-conversion landing page — a single page built for one service or campaign — usually costs between €600 and €800. It's the right choice when you have one goal: collecting enquiries for an ad campaign or a specific service.
How much does a full website cost?
A complete multi-page site for a business or professional practice usually costs between €1,500 and €2,500. The figure varies with how many pages you need, how many services to present and which features to integrate (bookings, qualified form, multilingual).
What pushes the price up?
- Multiple locations or professionals to present.
- Private areas, back-office integrations, e-commerce.
- Content in several languages.
These "custom" projects start where the full site ends and go to quote, because every case is different.
How to avoid surprises
Always ask for a written quote before starting, with price, timing and what's included. Be wary of anyone who publishes no price reference at all: transparency is the first sign of seriousness.