Hi legalassistant,
Acrobat Pro can definitely create reduced-size PDFs, and optimize PDFs to bring the file size down even more (and you do need Acrobat to bring down the file size). But, without knowing how large your original files are, it's hard for me to say that they can come down to 5MB or less. How large are the files are you working with.
You are welcome to download a free 30-day trial of Acrobat and see how it works for you. See www.adobe.com/products/acrobat.html for more information.
Best,
Sara