For piano training Yamaha’s GHS keybed isn’t the best choice in this price range..
Same goes for the actuall piano sound quallity
Kawai es 110 and or Roland fp30 make more sense and are conceived better choices in his price range

This answer is not only based on my personal opinions, but also on questions asked and answered on the piano players forum. Almost everyone there gave this advise, including piano teachers..

He could also try and find a used kawai es100, which offers nearly identical sound to the es110 and the keybed is even perceived better..