Your actual amount for the year 2018 is £900+VAT.
However we have given a discount of £300 on the yearly payment.
Discount on ongoing development charge £100 from £500.
We have also waived off last 2 months due payment = £216. 
But if you pay us 1000 today, we will waive off total discount £616 from that.
Now your total balance for the year 2018 is £1000+VAT= £1200.
After making the payment, I will be sitting with you thrice a year against the further development of the website and I will make sure that your website will certainly generate the most desired revenue. If this does not happen, then we will bear the loss.