Lisbon ArchiCAD Summer School partnered with Radisson Blu Hotel Lisbon to provide attendees with a special rate of 120€/night for single bedroom and 130€/night for a double bedroom from September 24th to September 30th. This is the nearest hotel to the venue (less than 5 minutes walk).
You can also contact our friends from Surf Lisbon – House & School. Besides being a Surf School with certified instructors, the best and adequate surfboards and wetsuits, transport to drive you to the beach, they also manage a Surf House in Lisbon – a XIX century house, beach front, with private and shared rooms, fresh breakfast served combined with a surfing environment and high standard of quality services. Send them an email to email@example.com and make sure you tell them you are attending Lisbon Archicad Summer School.
Otherwise check Airbnb and similar websites for other options.