Originally Posted by
MJJ
There's no point buying armour with it if you're not going to do anymore combat after Slayer.
It's up to you if you feel like skilling or boss hunting after Slayer.
If you feel like Skilling, then you could buy a 99. I don't know what your stats are, so I'm not sure which ones you could afford. Or, you could spend the cash on all of your skills and go for all stats 80+ or something.
If you want to do some boss hunting, then you could buy a godsword and try out Bandos and Dagannoth Kings for a while. You could make some of your cash back, and once you're done with boss hunting, you could just sell the godsword again.