When using the bot you only send 0.02, but the bot isn't really for guild members the way I understand it. As a guildy you comment on post with Hive account@earthnation and #boost, #superboost, #ultraboost, #megaboost. Also send Hive account@earthnation SBD with the post url in the Memo.
#boosts cost 50 GCs (for a 1$ upvote) and user must send 0.001-3 SBD with message
#superboosts cost 250 GCs and user must also send 3-9 SBD with message
#ultaboosts cost 500 GCs and user must also send 5-15 SBD with message
#megaboosts cost 550 GCs and user must also send 9-44 SBD with message.
SBD sent is used to purchase upvote bots. Members cannot use outside bots on posts boosted through the guild.