"Crash pad" is a phrase used to describe a place to sleep or rest temporarily. However, if you're looking for other synonyms to describe this type of accommodation, there are a few options. "Flop house" is a term that can be used to describe a low-budget, communal living space. "Squat" or "abandoned building" can also be used to describe a temporary dwelling. "Hostel" is another inexpensive lodging option that often offers shared accommodations. If you're looking for more upscale options, "boutique hotel" or "design hotel" may fit the bill as well. Ultimately, the synonym you choose will depend on the specific type of temporary lodging you're referring to.