There is not such restriction in Islam about getting the permission from first or second or third wife. Practically in this day and age I do not think that any sane man will be able to handle bickering and fighting of 4 wives. If you have faith in all the sahih ahadees then you will find out that even the wives of Holy Prophet(SAW) were jealous of each other and there was friction going on in that Holy family. I can provide references if some one so desires. That being said if one has four separate homes for four wives that man will be in big trouble dealing with the logistics of maintaining four households. If all four live in the same house then he will be dead in no time due to stress. I know some people who had two wives back in Pakistan their life was not very rosy, they were under high stress constantly.
I hate to be the one to say this Mirch but why is that? It sounds so...upsetting? Is there some sort of hidden rule Im not seeing here? Why can he bring another wife into the home without his first wife's consent?
Ive heard both rules...you DO need permission and you DONT. I know following religion is never easy...some parts are harder than others but I just dont understand this.