My form isn't calculating subtotal or requiring payment.

Here's my form: https://www.jotform.us/form/63544902535154?preview=true

I can't get it to correctly calculate the subtotal, and it needs to require a PayPal payment before it allows a form submission.  I can't even get a PayPal button to appear.  How do I do this?

Note- PayPal is setup as a User Defined Amount, which is supposed to be grabbed from the Total Cost field. 

I would suggest you delete the condition marked in the image below.

Then, add a Form Calculation widget to your form and add the "Textbox Field (id76)" in the calculation area. Also, make the widget hidden on your form.

Then, on your PayPal payment wizard, select the calculation widget as the "Get Price From".

Then, save it and save your form after.

I hope this helps. Let us know if you need any further assistance. Thank you.

Thanks for your help!  That worked, and it is calculating correctly in the box to PayPal, however there is no link for someone to click and pay via PayPal.  How do I add that?

By clicking on Submit button, the form will be redirected to PayPal. Since you are using custom calculation to pass to PayPal field, the option 'Use PayPal Checkout Buttons' in the payment field settings may not work. However, you may use the following link in the Button image option of Submit button so that the image will be displayed instead of Submit button.

https://www.paypalobjects.com/en_GB/i/btn/btn_buynowCC_LG.gif

Hope this information helps!