Five things to ask for
Live URLs, not screenshots. A picture proves someone can design. An address proves the thing shipped, loads today, and survived contact with a real client and real content. Ask for the address bar, then open three of them on your phone.
The parts the client can edit without the developer. Ask directly: what could this client change themselves? If the answer is “the blog”, everything else is a maintenance dependency you did not agree to buy. A site built on collections hands you the keys; a site built as static pages hands you a retainer.
A page they did not design. Building someone else's design is a different skill from building your own, because you cannot quietly simplify the bits that are awkward. If every item in the portfolio is theirs end to end, you do not yet know how they handle a file they did not draw.
Edit access from day one, not at handover. Watching the site get built is the cheapest quality control there is, and a developer who is comfortable with that is telling you something.
What happens after launch. Who fixes a broken form in month two, at what rate, and how fast. This is the question that gets skipped in the excitement of starting and remembered in the panic of a Friday.
What “custom” should mean
Custom is not a visual claim. Every agency says custom and means “we did not buy a template”. The useful meaning is narrower: what happens when your business needs something the platform does not do by default?
Imperium Completions is a studio selling bespoke web work, so its own site had to carry a hero that no template ships, a 3D object lit and rendered for the web, weighed for page weight before it was made pretty. That is the test: not whether the layout is unique, but whether the awkward requirement got built or got talked out of the brief.
The red flags
No live links. There is always a reason: NDA, client took it down, still in staging. One is plausible. All nine is a pattern.
A price before a scope. A number produced without asking what the site has to do is a number that will change, and the change will not be downward.
No named process and no dates. “A few weeks” is not a timeline. Ask what happens in week one and what they need from you to keep it.
“We will sort the CMS out later.” Content structure is the one decision that is expensive to reverse. Later means never, or means twice.