You will instruct UK lawyers to prepare the UK Terms of Business setting out your terms and conditions, which are usually subject to UK law. They should be as clear and succinct as possible, preferably able to be printed on the back of one sheet of A4 paper.
Should an overseas parent seek to impose their country’s law on a UK customer, it may risk not obtaining the work due to reluctance to potentially having to pursue a claim outside the UK. This also applies to UK branches operating in the UK, where the contract is between the foreign parent (of the UK Branch) and a UK customer.
However, the main point so often overlooked by companies setting up in the UK is Terms of Payment specifically for the UK market. UK companies are used to paying at 30 days from date of invoice, or on presentation of invoice.
If giving generous payment terms is part of the sales strategy, then that’s your decision. Otherwise seek advice as to what might be acceptable. You may be pleasantly surprised, and it could benefit your cash flow.
The method of payment is generally expected to be electronically nowadays: cheques are becoming less common. Settling invoices and paying employees can be done by BACS, CHAPS or transfer directly into their bank account.