Limited liability only works up to a point. If you want an overdraft from the bank they will make sign for it personally.
Yes a business number does add to your perceived size.
Best price I got was £600 for accountant but you can pay much more.
Things you will need doing.
- Personal tax return (Self Assessment)
- Corporation tax return
- Payroll, payslips and P35 (for you if only employee)
- Companies House return