Calculation Field double counted in total & other issues

I have a form for a design service where a homeowner can order photo masking for a design application or a floorplan service. I have a calculation field based on a quality level (basic or pro) and on the number of layers someone wants us to mask on the photo (1, 3, 5). The form calculation is:
{Quality Level Desired:105}* {Number of Layer Masks (up to...):107} for each photo uploaded.

On the form, when I had an Option field for the Quality Level, the total for each photo scene, and then the total at the bottom of the form was correct, but when I sent it to paypal it was double counting. When I changed it to a product field, it is now duplicating in the total at the bottom of the form. So, I am obviously doing something wrong. The floorplan service oks ok...and I even have a variable pricing based on the size of a property and it calculates that correctly.

I have also tried adding a product for Masking Service at $0 and then a product option at the $14.99 and $29.99 and then in the calculation taking the option times the level....and it still is duplicating the amount when you go to paypal.
Right now I have a product field as my option, which is either basic or pro quality masking level. I have prices in these fields of $14.99 or $29.99. On the number of layers, I have a drop down of 1, 3, or 5 and no values. The calculation is the product of the quality (basic or pro) * number of layers (1, 3, or 5). So it should be $14.99 or $29.99 if I just had 1 layer. It is showing as $29.98 or $59.98.

I can PM an account login which might be the fastest way to look at the issue.

Also...I was going to use woocommerce for more of a shopping cart functionality...but that might be overkill. I would like to show users what they ordered in terms of the design service somehow in their account....ideas on how to do this without a shopping cart installed?

ANother issue is I have a multi select field with 5 or 6 things in it. If the user does not complete a required field, the form refreshes with the error message...but it does not save the user's selection for the multi field....and it populates ALL answers in the field. So unless they catch it, they will submit the form with all answers.

Finally...do you have suggestions on how to handle a failed paypal transaction. with the easy way to do this...the form gets submitted, but in GF it shows as processing if the payment failed. It would be good to be able to keep the entry and try to resubmit it manually.

The form is at http://homediary.com/design-service/ however it is currently locked down...so I would have to send you a pm with admin login details....

I have gone to another site I have and tried to just recreate the options, quantity and product fields. See this page http://floorplanonline.com/form-test/
The code I have is as follows:
Quantity Product Field: options 1, 2, or 3
Option Field: Basic ($14.99) or Pro ($29.99)
Calculation Field: (Quantity * Option).
If I use the merge tags of
{Product Name (Price):1.2} * {Product Name (Quantity):1.3} the Product Price does not display anything....but the total does total up correctly.

If I use the merge tags of
{Quantity:2} * {Option:3} the product total will update with the right price for the options selected, but then the total is double counting the total. The total does not display on the screen but when you submit the form, it does double count the total calculation.

So it seems something is not working correctly with the calculation field, as I have narrowed it down to 2 options to get the product total and I still can't get it to work correctly.
I really need help...where is the documentation...as seems like it would be easy but nothing is working...on 2 different sites with different plugins.

Ok, I see if I make the quantity and quality (which has a price associated with it) regular dropdown fields vs use the product fields, then the product total works, and then the form total works....but
1. what is the point of having the product related quantity and options fields then....and 2. how can I get the price to show for the option (Basic being $14.99 and Pro being $29.99) on the form. With the Product option, it would show the price if I used the radio button - like if I selected on, then it would say +$15 on the other.

It seems like you should be able to adjust the total field to a calculation as well so you could just add up the product totals....not the product totals and then the options associated with those products. It seems counter intuitive....to me.