I agree that you will likely get cheaper prices waiting and saving, but that's not always easy to do. Some things you can buy now that won't fluctuate in price much or be obsolete in a few months:
PSU, Case, any kind of cable mods, uv strips, RGB fans, and cooling system. Most good AIO coolers will be covered for current and new CPU brackets even if you have to request a bracket later.
Ram is iffy. Its definitely high right now but not sure its really going to be much cheaper in a few months.
Storage drives, any cheap 7200 rpm drive is not gonna go much cheaper.
SSD, just have to catch it on sale. Caught a 960 Evo 500GB for $185.
CPU, MB, GPU should definitely be last.