Selling toys individually will maximize the money you can make.
If you prefer to sell toys in groups.. the best thing to do is group some good pieces with the less popular ones so that they will move.
Always be careful about buyers asking you to ship first or if they pay half up front then pay the other half after you ship.. ALWAYS get the full amount from the buyer before you ship anywhere.
when you do ship.. always do the insurance, tracking and anything else to cover your ass... you never know if a buyer will get the items then file a dispute to get the money back, screwing you over the process.
I hate to be negative about this whole buying/selling but do what you can to cover your ass