You buy a spot on it, and then depending on the row, you either get 1 gold per decoration or 1 gold per dress. Is that right?
Yes. You get extra money every round, when you collect income.
It seems pretty expensive to place in the fountain, so it seems like it would take a while just to break even. Are there even that many spots for decorations?
The decoration spots are not as good as the dress spots, which is why they cost less. It might take a few rounds to break even, but in later rounds the fountain can provide significant income. If your opponents grab fountain spots and you don't, you will likely regret it by the end of the game.
Also, one thing the videos seem to not be consistent about is whether or not one player can grab up all the fountain spots by himself, or if he's limited to one or one row. Can someone clarify? Thanks.
You are limited to one per row.