What does a “low spread” actually mean?

I used to think comparing brokers was as simple as finding the one with the lowest advertised spread.

It turns out there’s a bit more to it.

A spread is only one part of the trading cost. Depending on the account and instrument, you may also need to consider commissions, overnight financing, and the actual spread available when you place an order.

For example, suppose a pair has a 1.0 pip spread and you're trading a position where one pip is worth roughly $10. That's about $10 of spread cost when entering and exiting, assuming the spread remains unchanged.

That number can look very different during volatile periods.

I've seen people compare brokers based on a single advertised spread without checking the wider pricing conditions. avatrade is one example where I'd still want to check the specific instrument, account type and jurisdiction rather than assuming one published figure applies everywhere.

How do you personally compare trading costs before choosing a broker?