re: How about a shelter? Or getting under the surface?
Hey, the surface of Venus has been hot for at least a billion years. The ground is hot, the gravel is hot, the sand is hot, the rock is hot, the air is hot.
Diurnal temperatures vary by only a fraction of a degree. This isn't like the Gobi desert where you can hide from daytime heat and nightime frosts by digging down.
You're at the bottom of a gravity well, at the bottom of a supercritical sea of scalding carbon dioxide.
Best bet is to have lots of insulating material, and run a multi-stage heat pump.