Joomla component - php price modification

We have joomla booking component. Joomla 3 – booking component name is Koparent ([login to view URL]). We have an issue that this component didn't predict.

What we need it in backend - reservation part modification where is price calculation that is now default done. We need this fields that we can edit the values. Now is autogenerated prices per some price list for each advert and this is okey but we need to have posibility to enter other values in calculation,.

What we need is next:

1. We need to be able to edit – overwrite/modify the total price in final step of calculation in component backed

2. We need to have new field Discount where we need to enter some percent for example 30% and the total price will be automaticly decreased for minus 30%.

As well pls check full description of the project in attach

Joomla PHP

Projektin tunnus: #10291724

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