Ditto to bweybright's question . . . mileage on bearings?
Maybe jack up each side of the trailer, using the correct jack points, and spin each wheel by hand. Listen carefully for possible "bad bearing" sounds, and observe wheel-spin true-ness, integrity etc..
If the bearings were maintained correctly . . . should be fine IMO. We had a 25' back in the 90's . . . a great length IMO.
Do you have the impression that the current owner was careful about maintenance? Service records available? Stored in the dry desert environment? Any visible rust, where there should be none?
Let the music lift you up . . .
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