Having had the opportunity to work on a new build using Magento 2 the architecture of the application has changed significantly, to me it has definitely increased the difficulty of getting a Magento project up and running but in return offers a more granular and organised application to work with.
With this view I think it’s unlikely that you would upgrade your site to v2. Magento have not given an upgrade path to 2.0 and I doubt they will, so it’s probably worth waiting for the opportunity to re-design the site before moving over to the new platform.
Magento have committed to 3 years from general release of 2.0 so that gives you till around 2019 to move over. In the meantime that means they will continue to provide security patches and support for the 1.x platform.
Recently in my price matching system I had to calculate the selling price of a product in a way that also calculates a transaction fee percentage on the final selling price without knowing the selling price, and without knowing what the transaction fee is until you’ve calculated the total price. Had fun chasing your tail yet?
You can do this in Excel with circular references but you will get circular reference warnings and the only way is to allow these warnings and an iteration limit of 100.
Stepping aside from the magic of excel I was able to work out the exact formula for this and below is a calculation for anyone else struggling to work out how to do this.
$cp = 9.56; // cost price
$d = 2.50; // delivery fee
$m = 0.15; // margin 15%
$tf = 0.019; // transaction fee
$sellingPrice = (($cp+$d)*(1+($m)))/(1-((1/6)+$tf)*(1+($m)));
$costPrice = $x / (1+(.15));