Fix some website features

I have a website where you can design custom dress shirts. I need to install these features onto the website [login to view URL] 1) Already have ssl certificate purchased need to install it on the website 2) Need to replace the shopping cart completely 3) the website alignment is out need that to be fixed... when you go on different browsers it is not displayed properly. 4) Need to add some content and fix some spelling errors. ( I will provide the content) 5) The Dress shirt customizer options need some minor changes... for example when you click on the wide spread collar option it changes but the picture displayed is of a button down collar (when you look at the code we can discuss this option later) 6) The collection tab on the website is not working properly when you add a shirt to the shopping cart it shows the correct shirt but the wrong details of the shirt. 7) Gift Card option is working but there is no way for me on the backhand to create a gift card code or give out as a freebie to clients. 8) I would like the option of being able to generate custom coupons for customers ... currently i can just reduce the price of every shirt in the backhand system which gets annoying. 9) I have Olark installed onto the website but does not seem to be working. 10) I would like the option of the newsletter option mailchimp or whatever option is better to be installed so i can send out emails to the visitors. 11) The pop up on the side for the newsletter needs to be replaced as well. 12) When customers sign up I would like to change some options and the ability for them to save their measurements once they log in. Only serious inquiries and people who have advanced knowledge in all this. There is a lot more work to be done and I am looking for a long term relationship