He is in marquee but stil I don't think he will go beyond 12cr.
I don't think RCB will go beside Buttler but they definitely go beside Indian talents like Mayank Agarwal, Rahul Tripathi, Bhuvi, Siraj, Chahal, Sunder, Mahipal And in foreign they might target Will jacks, Stark, Stoinis, Glenn Phillip, Jack Fressar, bolt ect.
My dream XI for RCB is
KL Rahul (Wk & C)
Mayank/Rahul Tripathi
Virat
Rajat
Will Jacks (RTM)
Stoinis
Mahipal/ Sunder
Stark/ Boult
Yash
Siraj (RTM)
Chahal
Impact Player:
Bowler
Swapnil Singh
Akashdeep/ Vaishakh Vijaykumar
Batter
Sarfaraz
Anuj Rawat
Note: All the '/' option are if one buy is not possible then another as replacement or alternative option.