Getting a scanned contract under 2 MB
Many upload forms stop at 2 MB, and a phone scan of a ten-page contract is often five times that. Nearly all of that weight is the page images, so that is where compression does its work.
What compression throws away
A scanned page is a photo of paper. Compression stores that photo at a lower resolution and with less fine detail, so paper grain, faint pencil and soft shadows go first. Typed text stays readable long after that, because its edges are large and high in contrast.
When it starts to show
Small print, signatures and stamps blur before anything else. Zoom to the smallest text on the page at full size. If you can still read it without guessing, the file is ready to send.
The three steps
Compress the original scan, not a copy that was already compressed. A second pass loses detail again and saves very little space.
Then what
If no level gets the file small enough, Split can cut the contract into parts under a size limit. If you are starting from photos of the pages, Scan cleanup straightens and whitens them first, and a clean white page compresses far better than a grey one.