Just about all businesses need additional finance at one time or another. Maybe they are having a lean period but have contracts on the horizon; perhaps they have a temporary cash flow problem but know that they will be paid in the nearest amount of time; or maybe, on a more positive note, they just need money to grow their business and expand.
Whatever the need for immediate cash to inject into the business, make sure that you do your sums properly and make sure that it is not just a case of pumping good money after bad. Prepare a sound and solid business case for needing finance and ensure that you understand it and are yourself convinced of the necessity before looking to secure outside finance. Factoring is one way to obtain extra funds in a short amount of time. Put simply, if you have invoices due to be paid to you on a certain date, you can 'sell' these invoices to a third party who will pay you up front for the invoices, taking a percentage themselves for the service.
This is an established way of doing business and in fact many large firms do this as a matter of course.
Other ways to look at are bank loans and other financial institution loans, although you should always be wary of high interest rates however desperate you are.
