- Set up Column Gap
- Draw a rectangle (or with the loaded curser of several files) and lick the arrow keey up and right to increase the grid's number.
InDesign has an Align panel that lets you both align and distribute objects relative to themselves, the page, or the margins, and most of the he controls are duplicated in the Control panel.
But since you may want to havea variable number of ads I would recoomenr that you DON'T add the frames to the master page, but instead add some guides. You can add column guides during page setup, or later using Layout > Margins and Columns.... and you can drag horizontal or vertical guides from the rulers to any position you need at any time. I would add a basic set of guides to each master page.
There's probably a way to do it with key strokes or panels or a script or some other labor-saving trick.
But the easiest I can see is to create a layer on your template (you ARE using a template, right?), and use guides to mark off the areas where the ads would be if there are all four of them on the page. Name this layer "quarter page ads guides." Hide the layer, and lock it.
Then, when you get to a page that needs quarter page ads, turn on the visibility for that layer and arrange the ads. Then turn off the visibility. You lock the layer so you don't inadvertently put an ad on it.
You can also use the Edit > Rulers Guides settings to make the guides for those ads a special color.
Finally, when you need to add a quarter-page ad to a page, turn on the layer, add the ad (or ads) and then turn the layer visibility off.
You can use this layer on as many pages as you want.