Tool for Image upload, crop, preview and link to paypal

General information for the website: Custom Wallpaper
Num. of web pages/modules: 1
Description of requirements/features: Users get to upload their own picture, set the sizes of their wall and crop the image

Tool should work as follows:

step 1 - upload your own picture (jpg only) this needs to be checked that it is over the min file size and min resolutions
step 2 - give size of the wall (height / width) you want the image to be printed on too and also select from a dropdown list of paper types eg. Self adhesive, pasteable
Step 3 - Crop the image to the size / aspect ratio set in step 2. You should then see a preview of your cropped image on a wall. so using an image like this (http://hdw.eweb4.com/wallpapers/5786/) put the cropped image in the wall. At this point the user should see a price. This price is based on square meters and postage costs. user should be able to zoom in / out, rotate etc the picture on the wall so they see what they're getting. The quality should again be checked when zooming in / out.
Step 4 - Once confirmed there should be asked for name, email, confirm email, phone number, address line 1, address line 2, town, county, post code etc. and there should also be an 'agree to T & C' box they must tick. On submission it should save the cropped image and user information before sending them to Paypal to complete the payment.
Step 5 - an error or thank you page depending on the response from Paypal.

I need an email on completion with all the user details, sizes etc. and a link to both the original and cropped image on the server so that I can fulfill the order.

I need to be able to easily change:

min file size
max file size
min resolution
max resolution
image types (incase I decide that png / gif are ok to use)
price per square meter
postage

You can combine steps on to the same page if you want as long as it is simple to use. eg. step 1 and 2 could be combined

The whole thing should have a progess bar so the user knows where they are in the process and also be able to return to each step if they need to make changes.

This needs to be very easy for a consumer to use and very interactive. I suggest a combination of jQuery, AJAX and PHP as it will be going on a linux server.

There must be checks throughout the whole process to ensure all fields are filled in correctly (both jQuery and PHP validation)

This is a standalone tool that should look simple and be responsive. Please use bootstrap.

To give you an idea, it's like this but better :-)

http://www.photowall.co.uk/photo-wallpaper/custom
Specific technologies required: jquery, php, bootstrap
Similar urls: http://www.photowall.co.uk/photo-wallpaper/custom or you can search for websites that do printed wallpaper
Extra notes: