I'd invest all of the 999m gold into a bunch of underpriced SOS/SOM/SoSUN, resell and turn it into maybe 2 or 3 billion. Wash, rinse, repeat. Maybe after I get 5 or 6 billion, I'll buy myself a really nice 7D sun blade and 8D sun blade so I can level faster, give tons of gold to friends and guildies too.
Missing the good times in SRO...
SRO: 1x, STR Blader (Thebes) 54, STR blader (Venice) 0x, INT wizard (Venice) 19, INT spear (Venice) 34, STR rogue/bard (Venus) 0x, STR blader (Venus) 8x, INT bard/cleric (Gaia)