to bring my girlfriend from the philippines to australia, is it better to obtain the visa from the philippines or get it in australia

Hello Everyone! My girlfriend wants to travel to Brazil next year for carnival, and would like to use a travel agent to plan our arrangements, while I would much rather plan everything on my own using the internet as a primary resource. Could anyone tell me the benefits and negative aspects of using a travel agent to plan a vacation of this type? Also, I would really appreciate it if anyone who recently traveled to Rio De Janiero could share some opinions and perhaps “insider” tips on traveling to this destination. Thank you.