I'd say apply the procedure on pp. 58-59 of the PHB (yeah, I know it isn't SRD, but it is WotC...) You apply the Ability Score increase from leveling first, then after that apply the class features...which would include the extra point buy.
Seems to me like it would make a lot more sense to take a level of this class early than late. If you were trying to buy up the same stat, it would cost you less when the stat was a 16 or so than it would after several levels when it had been increased to a 20.
Seems to me like it would make a lot more sense to take a level of this class early than late. If you were trying to buy up the same stat, it would cost you less when the stat was a 16 or so than it would after several levels when it had been increased to a 20.