Bookkeeping to enter invoices on Sage England base only

I'm looking for someone/a company to do my company's bookkeeping

I'll like to be able to send you all invoices by courier every month,
You will enter the invoice in our on-line sage.

When done, you will send the box to our accountant (we will provide the labels).

We have around 100 invoices a month and take 1 to 1h30 to do 1 month.
The invoices have VAT and also non VAT (for children costume) but I will provide help for the first month.
Sage is already set up with all supplier and default accounts to use.

If the work is satisfactory we will do a next level by reconciliate our invoice again bank payment.

Due to the fact I need to send the invoice by courier, I will only accept England base person/company.

With warm regards
Alex