I am not familiar with this particular model. I had a 350E about 6 years ago and traded it in on the 15000. I do like Janome embroidery machines but the 350E had to small hoop for me and I wanted to do larger things, plus I fell in love with the 15000 and since it was a sewing/embroidery combo machine, I traded the 350 in to my dealer.
Have you done a google search for the Janome 400E? If you do that I am sure you will find pricing, the age of the machine, and reviews that will help with your purchase decision. Is this your first embroidery machine? If so you will need some training. Does the shop offer training classes for this machine?
Good Luck!
Here is a link to the Janome website with info on the 400e
https://www.janome.com/machines/embr...ry-craft-400e/