One channel, tight targeting
Search, exact and phrase, on terms that describe your product. No Performance Max, no Display, no broad match. You want to know whether demand exists and what it costs — nothing else.
Why not start broad
Broad reach with no conversion history means Google explores with your money, and you cannot tell whether a bad result is the product, the targeting or the learning.
What boring buys you
A clean search terms report, a real conversion rate, and a cost per order you can trust. From there every subsequent decision has a foundation.