Responding to the comment that using Church property or facilities are for purposes of the gospel, and that borrowing them for personal use is selfish... The Church allows, and in some cases even encourages, use of the building and resources for broader "gospel use" such as birthdays, scouting, book club, even Kids day at the church (play time for young kid meetups with parents in attendance). All of those can be stretched to be thought of as gospel related, but certainly they don't fit a tightly defined "gospel use" scenario.
If Church buildings can be used for birthday parties, book clubs, etc., then I think the Church is very reasonable in use of physical property and resources and I don't think using Church items for something like a wedding would run counter to that. If the concern, however, is that such items might not make their way back to the building, and for that reason should not be taken off premise, that I can understand.
To the question of whether items can be removed from a building for other uses, my understanding is the Bishop is the Steward for the building and makes this decision. But, as with others, the handbook is not terribly clear on the point.
I have been told by Priesthood Authority that certain items can be moved from one building to another, both permanently and temporarily. We did not need to consult with FM to make that decision.
