How do I handle tax and VAT?

You're responsible for your own tax. Trady doesn't deduct tax or NI from your payments — your monthly statement helps you with self-assessment. If you're VAT-registered, the customer-facing price is treated as VAT-inclusive (you handle the VAT accounting on your side). If you're not VAT-registered, you don't charge VAT and the price you set is the price the customer pays.