My memory is terrible, but spokes mysteriously "popping" on the older bikes seems to ring a bell. I'm sure it was mentioned on here in the olden days.
Anyway, if the front wheel hit something hard enough to break 4 spokes I would think other damage would be easily seen...
Also, Buchanan's is a well-known established business. I would imagine if they find anything else wrong they should let you know before they proceed.
Looks like you got yourself a good deal there. Welcome to the asylum.
