There's a reflex about the second sale that nobody states as a rule and almost everybody follows. Keep it small. Don't push. They just bought, so ask for a little.
The reflex has a real origin. A first sale to a stranger has to clear unknown risk, and a smaller number clears it faster. That's true, and it's most of why land and expand exists as a phrase.
It stops being true the moment they stop being a stranger.
The Rule Is Neither
The follow-on doesn't have to be smaller. It doesn't have to be bigger either, which is the same error wearing different clothes: somebody decides the account should grow by a target percentage and reverse-engineers an offer to hit it.
It's priced at what it's worth at the moment it's earned. That's a principle I've already put on this site, and I've been sloppy about its most useful consequence.
The number that principle produces is often larger than the initial deal.
Why It Runs Larger
Three things changed between the first sale and the second, and all three push the same direction.
The evidence exists now. At signing you were pricing against a guess about volume. Now you're pricing against volume that actually happened, and when you put a number on what that's worth the customer usually corrects you upward, because they're proud of it and because you were conservative.
The risk is gone. A small first ask is buying down uncertainty about whether you deliver. They've watched you deliver. You're not paying for that discount twice.
It's attached to something working. The second purchase isn't speculative. It's the next step in something that already has proof behind it, which is a completely different kind of decision.
Every one of those pushes the number up. None of them pushes it down.
My Own Offer Runs This Way
The Expansion Audit is $5,000. You can buy it outright, and some people will.
Most won't. Most start with the analysis at $1,500, and the audit is a $3,500 add-on after that.
The second purchase is more than double the first, and it's the easier of the two, because by the time it comes up they've read what the analysis found. What the analysis found is the entire argument for the audit. I couldn't have made that argument at $1,500, on day one, to someone who hadn't seen anything yet.
Same $5,000 either way. The sequence is what makes the second number unremarkable.
One Correction While I'm Here
Nearly every illustration I've used for this runs with an add-on smaller than the core. A $1,000 deal and a $600 item. A $150 line item that prices higher later.
That's an accident of the examples I picked, not a rule. If it's read as one, that's on me.
The Confession Inside the Reflex
Now the part that actually decides this.
If a second ask at three times the first strikes you as impossible, that instinct is information. It just isn't information about what customers tolerate.
It's information about what the first sale delivered.
A customer who got what they paid for, on time, with results they can point to, doesn't experience a larger second number as an imposition. They experience it as the price of more of a thing that's working. The customers who'd flinch are the ones you didn't deliver for, and shrinking the ask doesn't fix that. It just makes the failure cheaper to ignore.
So Size It to the Value
Price the follow-on at what the thing is worth at the moment it's earned. If that's a fraction of the first deal, fine. If it's triple, also fine.
The only number that's reliably wrong is the one you picked to avoid a hard conversation.
Lincoln Murphy formally named and popularized Customer Success starting in 2010 and has spent 15 years connecting it to expansion revenue and commercial outcomes. Read The Premise.