UK Flat rate VAT scheme - very popular in the UK

Hi, small businesses in the UK have the option to use the flat rate VAT scheme.  In summary, you invoice your customers with the standard VAT rate and you pay a fixed percentage of the total of the invoice.  VAT on purchases is not recoverable, except for large purchases (over a certain amount).

An example to clarify:

Customer invoice for 1000 + 20% vat =1200, recording a profit of 1200.

At the end of the quarter, vat due is 1200 * 13% =   156, recording an expense of 156.

I guess this could be done through a module.