I'm still running a 9 year old Dell Inspiron in which I have upgraded the RAM, added an SSD and switched to Windows 10. It still performs pretty well for basic tasks. Considering what it costs to upgrade these things though, buying a new laptop with all those on it already makes more sense. I would check Dell for special sales or on Dell outlet. I doubt accounting software is too demanding, so anything with a fairly fast dual core and 8 GB's of RAM should make a good replacement for what you have now.
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