There are some really cool amenities at apartments now.There are soundproof rooms to record podcasts and Tiktoks.Speakeasies.Gyms with Pelotons, Pilates classes and professional-level machines.Pools with cabanas, grills and fire pits.Pet spas. (And some even spas for people.)These are sure to attract residents—how could they not? But it's hard to win the amenities arms race. Can you even compete for ren ...