Room had a series of three windows, although it appears to look like one. The total span is around 10" with four single width panels - which are roughly around 50" finished width. I hope this helps.

Is this table available with leaves?

This table is from a company called Brownstone. It is their Sienna table. They only sell to the design trade, but you might be able to find it by doing a google search to purchase on a retail basis. Also,
Houzz did a feature on this table which will give you even more info - Cut and Paste - enjoy!
https://www.houzz.com/magazine/deluxe-expandable-dining-tables-make-room-for-more-stsetivw-vs~5191496

The faux finish on the columns, how was it done? Was this a painstaking manual job, or straight out of a can?

Hi Danielle. The finish on these columns was done by our professional faux finisher using several layers of various colors. Wish I had an easier solution, but that's how they were transformed. Good luck!