They’re close in meaning and often interchangeable. Nuances:
Attach the question particle to the predicate with vowel harmony:
As a sentence, the natural order is Subject–Predicate: Kargo tutarı makul.
Putting makul before the noun would normally make it an attributive adjective inside a noun phrase: makul kargo tutarı = “a reasonable shipping amount.” That’s not a standalone sentence by itself. For focus, you can front elements, but you still need a predicate structure (e.g., with olmak): Makul olur kargo tutarı (marked, emphatic).
Because tutarı already has 3rd-person possessive, further case suffixes use a buffer -n-:
Makul is common but slightly formal. Everyday alternatives:
Pluralize the possessed noun: