GoHighLevel books it. Jobber and ServiceM8 have it on the schedule.

Money tags, only when you switch them on

• Contacts synced with QuickBooks Online, Xero, ServiceM8, Simpro or WooCommerce can get tags.
• "customer" once they paid an invoice or a WooCommerce order, "overdue" while an invoice is past due.
• "job completed" after a finished ServiceM8 or Simpro job.
• Works with contacts one way into GoHighLevel or both ways.
• Off until you switch it on, because a tag can start your GoHighLevel workflows: check which ones listen to these tags first.
• "customer" and "job completed" stay; "overdue" goes once nothing is past due.
• No other tag is ever touched.

One opportunity per contact, unless you allow more

• A location that allows only one opportunity per contact refuses a second one for the same contact.
• Switch on Allow Duplicate Opportunities in GoHighLevel and it goes through on the next sync.

Tags power a filter

• Only contacts carrying one of the tags you choose start travelling out of GoHighLevel.
• A contact that already travelled keeps syncing even when the tag is removed.
• An opportunity, invoice or appointment of an untagged contact waits up to 30 days for the contact, travels once the contact is tagged, and is otherwise left alone until it changes.

One calendar, one team member

• Appointments sync into the GoHighLevel calendar you pick by its Calendar ID and new ones are assigned to the team member you pick by the Assigned user ID.
• Both are asked for once, when you add appointments.
• A reassignment made in GoHighLevel is kept when the appointment moves.

At most every 30 minutes

• A GoHighLevel sync runs at most every 30 minutes, on every plan, so the location's own API budget stays free for its workflows.

Invoices go out only

• Nothing is written into GoHighLevel invoices.
• GoHighLevel cannot list only the invoices that changed, so each run reads the invoice list; a sync from date keeps older invoices out.

Phone numbers in international form

• GoHighLevel only stores phone numbers with a country code.
• A national number gets its country from the address, contact or sub account.
• A number that still cannot be made international shows as a failed record.
• A phone emptied in the other system on a two way sync is emptied in GoHighLevel too.

Every contact needs an email or a phone

• GoHighLevel needs an email address or a phone number on every contact, so a contact with neither is not created there and shows in Activity with that reason.
• A phone number that already belongs to somebody with another email is left off a new contact, so two people sharing a number are never merged.
• In a location that allows no duplicate contacts, a contact without an email whose phone number another contact already has cannot be told apart, so it is not created and Activity says so.
• When an updated contact's phone number belongs to another GoHighLevel contact, the rest of the contact is still updated and GoHighLevel keeps the number it has.

One street line, country set once

• GoHighLevel has no second address line, so line 2 stays in the other system and is never wiped.
• GoHighLevel takes the country only when a contact is created; later changes stay in the system where they were made.

GoHighLevel invoices or won opportunities, not both

GoHighLevel invoices and won opportunities as draft invoices cannot both run between the same GoHighLevel and books accounts, in one integration or two, or the same sale would be billed twice.

Daily limits respected

• GoHighLevel has strict per location limits.
• Only contacts changed since the last run are read, the integration waits when GoHighLevel asks it to slow down, and when a daily budget is spent it waits for the moment GoHighLevel says it refills instead of failing.