wrong calculation of dicount/addition for payments

[chaosangel]

Hello Forum,

we have the following problem:
We are using Joomla 3.5.1 and Virtuemart 3.0.16.
In our different payments we want to give the customer a discount or an addition depending of the payment he choose.
For example paypal-payment is calculation with 2% addition.
In the configuration we put the value 2 in cost_percent_total.

When we have somethin in the basket with a value of 1000,- incl. tax and we are choosing paypal,
there has to be a total of 1020,-.
But in our case there is a total of 1024.29 !?!?
The other case is prepayment where the customer gets a discount of 3%.
With the basket of 1000,- the total with prepaymet has to be 970,-
But in our case the is a total of 965.34 !?!?

I do not know what happens and where i have to look for the error.

Can anyone give me a hint or a solution.

Thank you in advance for any help.

Dirk

[GJC Web Design]

is there tax involved anywhere?