If your business is doing high volume, low margin sales, then factoring invoices might not be your best solution. These are usually businesses that import an item to sell to wholesalers and distributors or computer re-sellers, or telecommunications pre-paid calling cards.
If your gross profit margin on a sale is less than 15% then factoring invoices will not work for you. We actually prefer profit margins in excess of 20% to feel comfortable that you will be able to afford the financing and continue to have suitable profit to grow the company.
Make sure you work with your accountant to understand exactly what your gross profit margin is on every sale. This is mandatory for a successful business.