Vidyamandir has the best study material, i did the same, no need to join any coaching if you don`t want to, believe me i am a victim of this, coaching may not suit everyone, i joined classroom course but found myself degraded at last when results of jee advanced 16 was out, some people are comfortable with their own style of studying Nd are not comfortable with other`s instructions,this year i had tried allen dlp which was sheer non sense in front of vmc`s buks, i went for vmc package and studied at home only and joined vmc and Allen test series, i am expecting 2500 rank this year, if you are allergic to coaching dont even think of joining it, its not necessary, surveys also say that almost half the successful students dont join coaching and if join they dont go for classes, but you must join atleast 2 test series to check regularly where you stand in competition. All the best (its only my personal opinion, it may or may not suit you, and if you are not joining coaching then be in consultat with a senior for guidance and solving previous years papers is a must)