On Saturday Melvin suggested that Jerome take the following week off from work and accompany him on a trip to the mountains.
Conclusion (It is clear)
Cost cannot be the real reason Jerome will not go to the mountains with Melvin.
Evidence (since)
Jerome gives the same cost excuse every time Melvin proposes an unscheduled vacation, no matter the destination.
Evaluate
We're not allowed to just reject someone's reason by saying, "oh, you always say that".
Jerome said he couldn't take next week off work to go the mountains because he couldn't afford the trip: the lost wages + cost of the trip were too much.
If our author is like, "nah, you say that every time", Jerome will be like,
Okay, I may have taken that too far on Jerome's behalf.
Goal
Look for an answer saying that the fact that "I can't afford it" is Jerome's excuse every time he turns down Melvin doesn't mean he's insincere. This is just a persistent problem!