He's only ever made one post and there was nothing about either of those in it.
You are 100% correct and the OP would do himself a favor by telling us more about what he wants to do. For example, he may want to tune the top four EADG, as normal, and just have the B string for some "drop B" tunes. In that case any fiver and any standard five string string set would be fine. But that might not be what he wants to do at all....
OP: Tell us more, tell us more, and we could help you. Otherwise you will get dozens of pieces of conflicting advice each based on the respondent's assumptions about what you want to do. Give us the five pitches you want to tune to and give them to us in
scientific pitch notation which removes all doubt about what frequency each string will be tuned to. The standard tuning for a four string is E1, A1, D2, G2. The standard tuning for a five string is B0, E1, A1, D2, G2.
For example I use the cello or fifths tuning C1, G1, D2, A2 on my four string basses and I add an E3 and B3 to my five and six string basses.