How many broker accounts should an active scalper keep?

[FXS London Scalper]

One account is simple. Two or three give flexibility. More than that becomes hard to manage.

Reasons to have more than one:
- Backup if the main broker has an outage or issues.
- Comparison of execution and costs.
- Different account types for different strategies (e.g. raw for scalping, standard for swing).
- Diversification of counterparty risk.

Reasons to keep it to one or two:
- Each account needs monitoring: statements, platform updates, terms changes.
- Capital split across accounts means smaller size per account.
- Comparing performance gets messy.
- More logins, more passwords, more ways to make mistakes.

A common setup among experienced scalpers:
1. Main account with the bulk of capital and the best execution.
2. Backup account with a small balance, tested monthly, used only if the main is down.
3. Optional test account for evaluating a new broker.

What's your setup? Have you ever needed the backup account in a real emergency?