Most people commissioning a website have been burned once already, and the damage is rarely the design. It is a deposit paid, a month of silence, a half-built site, and no clear way to get either the money or the work back. These are the questions that surface that risk before you pay anyone, including us.
"What exactly am I getting, in writing?" A proposal should name the pages, the features, the price, and the date. If the scope is a paragraph of adjectives, the invoice will be a surprise. Ask what happens to the price if you change your mind halfway, and get the answer before you sign rather than after.
"Who owns it when we are finished?" You should own the code, the domain, the hosting account, and the analytics, all in your name. If moving to another agency later would mean rebuilding from scratch, you are not buying a website, you are renting one. Ask specifically whether the site is built on a proprietary platform only that agency can edit.
"Can I update it myself?" Changing a price, adding a photo, or writing a news post should not require an email and a wait. If it does, ask what that will cost per change, and multiply it by a year of small edits.
"What happens after launch?" A site is not finished when it goes live. Ask who applies security updates, who is called when it goes down at the weekend, and what the response time actually is. "We offer support" is not an answer; "a named person, within one working day" is.
"Can I speak to the person who will build it?" If everyone you meet during the sale disappears after it, the people who understood your business are not the people writing your site. Ask to talk to the engineer, and notice whether that is a normal request or an awkward one.