The details.
If referrals already work, why have a website?
Because a referral is an introduction, not a decision. When someone hears your name, they may look you up before they call. What they find there can shape whether the referral turns into contact.
A website does not create word of mouth. It catches it. Without one, you are asking a referred person to take your name on faith alone.
What does a referred person actually look for?
Three things, fast: confirmation that you do what their friend said you do, evidence that you are real and current, and an obvious way to reach you. If any of the three is missing or buried, some referrals quietly end there.
You will never know how many. The person does not complain; they just do not call.
Isn't a Facebook page enough for that?
Partly. It confirms you exist, and it is better than nothing. But a referred person wants your services, your area and your number, and a social page buries those under posts, comments and the platform's own clutter.
There is a fuller take on this in the Facebook page versus website answer.
What should a referral-based business put on its site?
The things a referred person came to verify: what you do, who you do it for, where you work, some proof like real photos or named reviews, and a phone number that is easy to tap on a phone.
One page can carry all of it, and a single focused page is easier to build and to keep current than a large site.
When can you skip the website?
If you are booked solid and turning work away, it can wait. A website earns its keep when you want more inquiries, better-fit inquiries, or a business that still looks solid when the referral stream slows.
The wrong time to build one is in a panic during a quiet month. The right time is while the referrals are flowing and nobody is counting on it yet.