But don't go inside at the golf club, don't travel more than maybe 5km, don't use public transport, deep-clean the rental house when you arrive and leave.

Seriously, it's easy to think that sitting in a rental house for 3 weeks is harmless, but then you go shopping, and even with a mask you still have a ~10% chance of spreading it, and then you're spreading it to a community likely a significant distance from your own.