Can I filter or export a list of customers by how much they've spent?

Not directly, no. There's no spend or total-booking-value field anywhere on a customer record, so there's nothing to filter or sort the Customers list by. The Customers page and the Customers export both carry contact details only — name, email, phone, address, location — never a financial total.

Spend only ever exists at the reservation level (each booking's own price), and BRM never rolls that up onto the customer it belongs to. If you need "customers who've spent over £X," you have to build it yourself.

How to build it

1. Go to Reports → Export Data, set Type to Reservations (or Transactions, if you want it payment-by-payment rather than booking-by-booking), and choose your date range.
2. Open the export in a spreadsheet and build a pivot table: customer as the row, price summed as the value.
3. Sort or filter the pivot for whatever threshold you're after.

Two things to watch for: it only covers whatever date range you export, so a customer's true lifetime total means exporting their whole history, not just this month or this year. And if a customer has duplicate records, each one pivots separately — their real total is split across rows until the duplicates are merged.

See deeper analysis using spreadsheets (and pivot tables) for the general pivot-table walkthrough — the steps are the same, just summing price by customer instead of revenue by category.