Your points: 1. None really, it could be as simple as reciepts from one of those books you buy in WHSmith! But think of it as you receiving the invoice, the bare minimum you wouldwant is, Who they are (You or business name), Where they are (home or business address), What they had (courier services), and When they had it. Its that simple...! UNLESS your VAT registered, then there MUST be things like VAT number, Tax point ref number etc. etc.. full details can be fpound on HMRC's website.
2. You can produce invoices for each and every week if you wish, which IMHO is a waste of paper, or you can do one invoice for the whole lot, or maybe one for every month. Just put on each line the date that the service was used.
VT, Sage and QB can all produce invoices for you without having to reinvent the wheel.
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Shaun
Responses are not meant as a substitute for professional advice. Answers are intended as outline only the advice of a qualified professional with access to all relevant information should be sought before acting on any response given.
Not only that but with excel based invoices you have to keep track of the invoice numbers as well as remember what number your on... with the software option it does it for you!
There are budget invoice sofware makers out there, you could even try things like Kashflow or Xero, they are cheap (monthly) and have all the tools for designing templates!