Pre-sale question

Hi there,
I have a question about this plugin. We sell refurbished products and have a lot of variations.
We want to be able to enter the cheapest option just once and then let the plugin calculate all the variation prices which are always increasing by a set amount.

We have 2 increase rates, 1 is the grade of the product (condition) which increases the price by 20, 2 is the other variations (hard disk etc.) which increase the price by 30.

Is this possible? Also we use the sale price for the main price as the main price is used to indicate how much the product costs new.

Please let me know if the points above are possible with this plugin. Thanks in advance!