I have 250-page PDF file, which I would like to place into InDesign. Do I have to place each page separately, or is there a way to do all of them at once?
It's hidden away but it is possible.
1) File > New > Document
Enter the number of pages of your PDF in "Number of Pages". Deselect "Facing Pages" if you want individual pages. If you know the dimensions of your PDF, set that as your document width and height now, otherwise you can edit it later using File > Document Setup.
2) Window > Utilities > Scripts
So I wrote an AppleScript that does this. It has the option to place not just a multiple paged PDF but also a folder of images (which may also contain PDFs). If there aren't enough picture frames selected on the page, an option lets you duplicate the original page and continue filling the boxes until all images or pages have been placed.
Try it out and give me some feedback!