GigSpace tracks two sides of every gig: what the venue owes you, and what you owe the act. Both are derived from the gig, so they stay in step with what actually happened.
The act's payment is released once the gig is completed. Venue invoices can be issued per gig, or consolidated into a periodic statement if you set a billing cadence for that venue; the same works for acts.
VAT is handled at 23% where it applies, and the VAT screen splits what you've charged from what you've been charged so the return is straightforward.
You can adjust, void or credit an invoice where you need to. An edited invoice is protected from being overwritten by the automatic sync.
The ageing view shows what's overdue and by how long, oldest first. That's your chase list.
GigSpace never holds or moves money. These are records: you and the venue settle between yourselves.