always depends on how much you want it to do. I use Excel spread sheets to keep track of every thing. I have a word template that I use for invoices. But I don't need a line item program that keeps track of inventory as it is sold. Point of Sale software is what you need if you are going to do that. Any company that makes it is going to charge for it though.
Do your spreadsheets keeps a repair history by equipment model/serial as to what was done and what parts used for the past ten years. In the software I run all this is easily accessible.
Example of a work order that I just completed.
Sorry but the Adminsoft software I run is available as free software that is supported by advertising which only shows up as you exit the software and the one line advertising line for Adminsoft software on invoices.
Now Sales Prospecting and Sales Orders section are for registered versions only but all other sections are available in the free version.
There is a paid registration version. My current version is a paid version where I could remove the ad line on invoices if wanted to but I don't. I felt that it was better to support the programmer plus I get priority tech support when needed. I am one of his biggest users when it comes the amount SKUs (inventory items) price files on my system. I currently have over 954,000 items listed (includes supersedes, NOS, aftermarket crosses, and NLA items).
When I first started his price file imports caused problems due to the shear number of items being imported (over 150,000 items at a time) but he has resolved those issues of taking days to import 150,000 down to under an half hour. Then there were other problems we had to resolve related to superseding during imports as initially the program would lose bin locations during superseding. Now I have an option to transfer all data to the new SKU numbers. The option is really important to me as I have notes on the parts too that needed transferring to the new SKU #s along with associated parts lists.
And considering I have over 2,200 different items in stock I really need to keep the bin location on superseding or items will not be easily found.
And the programmer recently added Sales Prospecting and Sales Orders to the program set. I don't use it myself as I primary just use the Auto Manger portion and inventory tracking / pricing. The only thing that don't work is the Payroll section as that is only for the UK which where his company is located.
But as with all software there are things can stand improvements and errors can be introduced during updates (which are quickly resolved once reported); although, I am still recovering from one a couple years ago where all my inventory movements were compromised. That time I went from having $26K in stock to having $750K in stock. Now with problem corrected I am back down to $38K in stock with a few items still being reported as in stock when they are not. But this is fairly close to my actual inventory as I have added a lot parts during this time frame. I will be cleaning the shop wall to wall this Fall/Winter, doing another annual manual inventory check as I still have a few items without Bin locations do superseding, and building maintenance. And I might even inventory all my tools. I really should do that one for insurance purposes.
Also note I have been using this software since 2012 so it about to start dumping some the older info now.