If you're looking to save money, planning your own travel rather than using an agent is generally the best way to go. However, if you have special needs (like health issues or specific sights you want to see or things you want to do) a travel agent can save you time and help you find what you want.
Image from grassrootsgroundswell
Maxwell Williams, writing at Conde Nast Traveller, gives some common situations in which you'd want to use a travel agent.
- You're travelling with a large group.
- You want to attend a special event (like a limited entry exhibit or party).
- You have health issues that need to be accommodated (like not being able to stand for long periods of time).
- You need a the insight of someone who plans lots of different travel. For example, if you're short on time in a destination, want to go off the beaten path, or simply don't even know where to start.
To that, we'd add booking round-the-world or multi-destination trips -- while the online versions for these have improved, they rarely have the flexibility of a full travel agent.
If you need help finding a great agent, ask family and friends for their recommendations. Once you have a few picked out, you can search online to see if there are any reviews on sites like TripAdvisor or Yelp.
Why a New Generation of Travel Agents Matters More Than Ever [Conde Nast Traveller]