He is already using Tally for accounting and inventory in conjunction with my system. Even with a new inventory system, he will continue using Tally for accounting because it is one of the very few systems that mimics the actual accounting process from vouchers to journal entries to ledgers to trial balance to final accounts. It is Tally's inventory system that is the irritant. While its generic nature meets the demands of a single tier taxation/ discount system, using it in his case is akin to trying to force a square plug into a round hole - it doesn't hold up very well.Nothing wrong with GnuCash except the fact that it is more of a single entry accounting system than a double entry one. Most accountants would go mad figuring out what the hell it does with their transactions. Professional accounting has very specific demands from its software and Tally is the de facto standard as far as double entry accounting systems are concerned, at least in India. The second thing is that it is not an inventory system, which is what I am interested in.The sheer agony of editing 2500 inventory items if either the price or discount changes (some of it is unavoidable, but a lot of it is not) is what is the cause of a massive headache. A configurable system that takes care of the entire inventory process from order management to billing is what the situation demands, and I am working on it as time permits.