This is very poor onboarding experience by the employer. Not necessarily a signal that your future with the business is going to be bad, but also not a signal

This is very poor onboarding experience by the employer. Not necessarily a signal that your future with the business is going to be bad, but also not a signal to ignore either; there are elements here - lack of care (IT sending laptop), cavalier attitude to legality (being on customer calls before being employed likely does contravene some privacy laws) and poor inter-department coordination - which are likely to be endemic in the business. That said, it might be typical of a 'rocketship' business trajectory - it is and will be a bumpy, messy ride. The bottom line is does this type of messiness suit your working style / personality type? The answer tells whether to stay or go