Here are some things that I thought of, may or may not have anything to do with your venture, but they're points I would consider:
How are you identifying the apps that the business will need?
How/what appleid will you use?
Are you fronting the cost, or are the customers? (for iPad,app,accessories)
Will you offer accessories like cases, covers, stylus, appletv (for displaying at the office), etc
Have you thought of creating forms for the client dependent upon their business?
What research/questions are you asking to evaluate the client needs before purchasing and loading apps? (would you create apps or only load existing apps?)
If there are people "in the field" that collect info, how is it transmitted and processed back at the office?
Who will train the staff on how to best utilize the iPad and apps?
Are there industry/company regulations to consider regarding the security of loaded applications?
Is there a cost/benefit you can show to prospective clients? (save on printing costs?). How will using the iPad make your clients more efficient?