Ver. Ka. means version katoki.

This guy: http://en.wikipedia.org/wiki/Hajime_Katoki

Usually he takes some old mecha and redesigns them and Bandai makes more money.

Mod jobs like trimming down the legs to look sleeker, or making the wings on Freedom sharper, or adding weapons, or... too many to list really. If its exactly like the box cover, then I doubt its modded, mods usually go for a more unique look.

RM700 is kinda expensive btw. What kit is it?

I like the Unicorn, but maaaaaaaaaaaaaaaaan does it boggle me why anyone would paint a war machine white.