ACER Aspire TimelineX 4820TG for sale 400$

I'm selling my laptop only because I got a new one from work, therefore I don't need this anymore. It is quite fast, it has an i5 CPU, 4 GB of DDR3 RAM memory, a solid state drive. I never had any problem with it. I did quite a lot of MATLAB, C++ and Autocad with this, and with very good performances. It has windows 8.1 and can be upgraded for free to windows 10 (or you can use the licence key to reinstall win7). I'm asking 400$, but we can discuss about the price. The picture is from the internet, I can take a real one on request.