By channel, the honest clocks: paid search shows real signal in 30–60 days (setup, then a learning period); local SEO moves in 1–2 months; sitewide SEO needs 4–6+; email nurture shows engagement immediately but revenue over a quarter. An agency promising results faster than the channel's physics is promising, not planning.
What you SHOULD see fast. Within the first two to four weeks: tracking installed and verified, accounts properly owned and organized, a baseline report of where things stand, and the first work shipped. Process speed is visible immediately even when outcomes aren't.
The fair deal to strike up front: agree on the 90-day scoreboard in writing before signing. Which numbers, measured how, reviewed when. Then hold the review. Agencies worth keeping welcome that meeting; the others reschedule it.