When to start baby shopping?

Hello mummies! First time mummy here at 13 weeks. When is a good time to start shopping for the baby for essentials? Like strollers, baby cot etc. Also is it normal if i want to check on prices earlier on so I know how much to save up? Also any good place to recommend? Are baby fairs good enough? Also usually what is the frequency of a baby fair being held? Like once every 3 or 6 months? #pleasehelp #firsttimemom #advicepls #firstbaby