I am using My Invoices &Estimates, It can track items although that is not its primary purpose. This is a dual entry type of accounting program. It is a bit of a pain when something gets out of wack but it is a inexpensive program. No limit on # of invoices which is some what typical of most cheap programs. I have some experience with other complete systems costing a lot $$$$. If you do not need payroll that saves a bunch of cash. Some programs can be bought in modules- invoice, inventory, payroll, income vs expenses. The problem that comes up is how far the chipmakers push the operating system bit wise. I have an old complete system 8 bit( lot of $$$ wayback ( this is all on floppies ) it is no longer able to be run on todays equipment, had another program from the mid 90's and again it will not work with 64 bit systems. I really liked that one because it was a single entry accounting /inventory system and not sensitive to things like periods dashes slash marks ect. example- on current program entering a address like W. 89th Ave. would get you an error code locking things up. Those 2 periods can't be there in the address line. Common error as this is how you would properly write it