It is said in the walktrough that Oohlgrist, Chief of Trolls will join the Fire Temple for 10,000gp. Another solution is talking to him with a diplomatic character, then he will do it for free.
Frostband:
The big fight with with the Bassanio and the salamanders can be avoided. If your first strike at Bassanio finishes him off(would require a critical hit), the salamanders won't appear and Frostband is yours for the taking. I know this approach is purely based on luck, I just thought it was a shareable piece of information
