Do I need to rent a car?

Absolutely not. Driving in Lisbon is chaotic, parking is expensive, and public transport is far more efficient.

Is Tram 28 worth the wait?

Only if you arrive at the terminal (Martim Moniz) at 7:00 AM. Otherwise, it is just a crowded metal box.

How to see Lisbon in 3 days using public transport

Use the Navegante card for unlimited access to metro, buses, and iconic trams. Base yourself near a metro station in Baixa or Chiado to reach all major sites within 20 minutes.

Get the right transit card. Buy a 'Navegante' card at any metro station (cost 0.50€). Load it with a 24-hour pass (6.80€) or 'zapping' credit if you prefer to pay per ride. Do not buy single tickets from drivers; they cost double.
Master the hills. Lisbon is vertical. Use the Santa Justa Lift or the Glória Funicular, but always check the queue length. If the line is over 30 minutes, walk the parallel streets to save time.
Use the CP trains for day trips. For Belém or Cascais, use the urban trains departing from Cais do Sodré. These are included in your Navegante pass if you have the correct zone coverage.

Do I need to rent a car?: Absolutely not. Driving in Lisbon is chaotic, parking is expensive, and public transport is far more efficient.
Is Tram 28 worth the wait?: Only if you arrive at the terminal (Martim Moniz) at 7:00 AM. Otherwise, it is just a crowded metal box.