All three run from a few thousand euro to well into six figures, and that is not an evasive answer: the spread comes from what you order, not from who makes it. Before you ask for a price, you need to know the four dials that move it.
The four dials
How much gets made. A logo is not a rebranding. A rebranding is a logo, a typeface, a colour palette, photography guidelines, a tone of voice, templates for every channel, and the conversion of everything that already exists. That last item is almost always the largest and almost always forgotten.
How often it gets used. A campaign for one market and one channel is a fraction of the same campaign in three languages, four formats and six months of run time. Ask for a price per rollout, not only per concept.
How much has to be invented. A website on an existing platform with an existing structure is execution. A website that first needs a story, a structure and a conversion path is a strategy assignment with a website attached.
How many people decide. Every extra decision maker adds rounds, and rounds are the most expensive part of any creative process. Three feedback rounds instead of two can cost more than an extra language.
Why price ranges from the internet mislead you
They quote an amount without a scope. Someone reading "a website from 5,000 euro" compares it to a 40,000 euro proposal and concludes the second agency is expensive. In reality they are comparing five pages on a template with a custom site in three languages hooked into their stock system.
What to do instead
Put your budget in the briefing and ask what will be made for it. You then get three proposals you can compare on substance rather than on price, and you immediately see which agency understood your question best.
Also ask explicitly what is not included. Photography, licences, translation, hosting, maintenance and your own team's hours fall outside by default, and together they are rarely small.
Pinning down the scope starts with your briefing, and you can have that checked for free with IKAg's briefing analysis.
See also: what an advertising agency costs and what belongs in a pitch briefing.