It’s best to buy an umbrella on a sunny day.
You don’t need an umbrella when it’s sunny. It’s not urgent. So you can comparison shop, think carefully about your needs, select the best choice rather than the immediately available one. You aren’t running the risk of umbrellas being sold out at the store, and you aren’t going to be price gouged by a predatory street seller. (I talked one down €15 Euros to €5 in Florence two years ago, but he still made a good profit on the cheap umbrella he sold me).
It’s the same with any decision. In the heat of the moment, you can’t necessarily make the best decision, because you need to make the immediate decision.
What umbrella decisions can you make this week? Can you set side time to make decisions when you have the most flexibility? You’ll thank yourself when it starts to rain (or you start working 80 hour weeks…)