The only purchase I’ll ever advice anyone is
OG book from GMAT mba.com - basic cause of their Q’s and the rest, rely on this site.
Personally, I have noted that everyone purchases Advanced Quant from
Manhattan Prep so its advisable.
If you’re struggling with certain areas, then look into FORUM posts on tips for it. GMAT club even produced their own Quant book - notes for Quant.
If additionally do need resources, head to the FORUM, search, the entire team have a breakdown on pros and cons of suggested materials to purchase.
If you’re like me in a country where you cant get access to most materials -
Manhattan Prep is the only book you may be able to get your hands on.
Make good use of FORUM and the experts on this chat sites.
The only reason why I am active here is cause Im hanging in FORUM searching for something.
Please do not DM me with your number after seeing this msg though.