Here is my requirement :
I run a newspaper agency where i deal with 125 vendors daily. i am not connected directly with customers. I deal through vendors. These vendor comes to me daily and get their supplies ( supply may vary daily ).At the same time, they can return me previous day unsold newspaper copies. Some pay me cash daily and some are on monthly basis where i bill them for specified period ( deducting any amount they paid in meanwhile ). Newspaper cost may vary each day. Like on Monday rate of paper is 4rs and i get that at 2.44rs from press . i sell to vendor at 2.75rs. same like Like on sunday rate of paper is 5rs and i get that at 3.09rs from press . i sell to vendor at 3.75rs.I need to generate bill on 30th or 31st every month. they can pay me full or partial any day. I am attaching a screenshot where you can see how i am doing current entry in excel sheet. With the help of filter, i get bills currently. I need some software system for this. I want to access this from anywhere in world. But entry must be offline. Currently i am storing my excel file on dropbox. After daily entry in excel, i sync it on dropbox. If u can include mobile app access, it would be great.