Marketplace builder, Stockholm, now on the sponsor side of the table (Annonsplats matches sponsors to newsletters, I watch deals die daily). What sponsors ask, in order:
Who else is in? (Social proof first, always. Solo logos scare money.) What is the open rate trend? (Trend beats level. Rising 30s beat flat 40s.) Who writes? (A named human with taste. "Our team" is a red flag. Names convert.) What is the minimum? (Small tests first. 4-week minimums close. Annual asks die.) Can I see the bad issue? (Everyone shows the best. Smart money asks for the median. Have it ready.)
Founder-to-founder translation: traction, trend, human, small ask, honesty. The same five things investors ask, with newsletters instead of MRR. Money is money. Proof is proof.