I need a Magento Expert

General information for the website: Magento Bundles and customers seeing Cart double up at check out
Description of requirements/features: We are having 2 issues with our Magento backend .

1.We use the Bundle option to list on our site, but when we come to create the bundle it will not load, the only way we have found to fix this is clear old simple product with 0 stock this lets us bundle only the the amount we have cleared we only have 900 simple products with 0 left to delete once this is done we will not be able to create a bundle.

2. Many of our customers report their shopping cart showing double at checkout and they cannot complete paypal payment as the total does not match. The only way to fix this we have found is to clear cached items on their pc which works on 70% of occasions but this is only for the customers that let us know. also if the customer completes checkout while it is showing double when the order comes across it is correct not double so it only seems to be at the customers end.
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