If you are freelancer you probably try to save on everything and to reduce costs of your business. Sometimes freelancer do thing amateurishly. I think it is a mistake, which every freelancer should avoid.
When you do your own business as a freelancer usually some problems are caused by invoicing. Recently I was making some contract in MS Word. Oh, how complicated it was to put every line every part of text into right place. I spent plenty of time on that contract. The same is with invoicing. When you try to create invoice manually it takes very much time. Of course it is not a problem if you have some 5 customers every month, but with 100 customers it becomes complicated. So my experience showed that it is better to use invoicing software. It is possible to find relatively cheap invoicing program, because market provides wide choice of such software. Furthermore, usually you are advised to try software for free. It also let you choose the best program for invoicing.
The fact is invoicing program provides a lot of different features, so you will not use it just for invoice creating. Trust me it will become your best assistant immediately. Most probably you have some notes about your clients and products. I advise you to do it professionally like I do. I have special database into my invoicing software, where I save all customers in a very convenient way. It is very easy to use this information in future, because you can add it to the invoice by a few clicks. To my mind it is more pleasant to work, when you do things professionally. Even if I have small company or I am freelancer, I will organize my working process, so that it shouldn’t become chaotic. I remember when I was a freelancer the most hard was organizing working day. You know, when you work for yourself and you are both boss and employee, it is always temptation to take some hours free, that’s why freelancer should be very organized.
According to my experience invoicing software is the best for freelancers. On the one hand, it is simple enough to sign up and to start using. On the other hand no one will tell that you’re a freelancer, because invoicing is very efficient and professional.