OK, there is a limit here that you DO need to know about. Everything in report layout is based on sections, and sections have a limit of 22.75 inches high and wide. For standard 8.5x11 paper, if you have 1-inch margins all around, you have (8.5 inches - 2 x 1 inch margins=) 6.5 usable inches... x 4 = 26 inches. You cannot make a 4-page-wide report on portrait mode that uses the entire 4th page because the section can't be that wide. Section size is a hard limit that you will have a devil of a time in breaking. Note also that if you have things in landscape mode, that's (11 inches - 2 x 1 inch margins =) 9 usable inches and there, x 3 pages is 27 inches - again, over the section limit.
The basis for this limit is that Access uses a unit called twips for placement of objects. The unit is such that 1440 twips = 1 inch in either direction - horizontal or vertical. The slot that holds the width or length of a section and the slots that hold horizontal and vertical positions are limited to 16 bits AND cannot be negative, so the effective limit is 0 to 32767 as the largest positive 16-bit integer. If you do the math, 22.75*1440 = 32760, which is why you cannot get a section to go any wider or longer. If your design absolutely requires 4 sheets across (or 3 in landscape), you have a major problem using Access. Not impossible, as you COULD try to make two or three parallel reports, but getting them to stay exactly aligned might prove difficult.
The solution MIGHT be to export your data to Excel, which doesn't have the same limits because it does its printer graphics differently than Access does. You can get Excel sheets that are very wide and they can be made to print across multiple pages. They just won't look as pretty as an Access report can look.