CreLoaded custom contributions

We sell furniture online and have started using a Creloaded store but need some amendments to add some additional features I can’t find covered in any contributions.. One is a size converter to offer sizes in both inches and Centimetres & the other is to help calculate shipping costs. This is my first request on G.A.F and will be followed by a few others mostly contribution installs some custom. I would like to work with the same person / company if possible on future projects so signs of consistency would be of benefit. Product sizes We need to display sizes for all products Height / Width / Depth I know I can do this in the attribute section but want to offer the customer the option to select size in cm OR inches and for it to display the measurement type/prefix. (I also don’t want to have to input data twice can you set it to auto fill one measurement type based on the value of either, or one of the measurement type's for data entry?) Custom shipping module. The Shipping Services offered are dictated by three factors, Size, weight & location. Shipping Services offered: - TNT/DHL (Flat Rate per Parcel) Max single parcel weight is 30KG Max parcel size is (Longest side + (width x2 + depth x2)can = no more than 300cm NB. longest side can be no more than 150cm. Also offer the ability to combine shipping i.e. if the size/weight of two or more items is still less than max size allowed per parcel combine them. Courier (Priced by post code) Overall order size restricted to no more than 2.5m x 1.5m x 1.5m per van - Large Van 2 man job. (Priced by post code) Unlimited size. I will be listing the (MAX) height width and length of each individual item we sell so wondered if you could determine the shipping service based on their size/weight; and the cost based on location/service to offer the customer all available delivery options. Alternativley I have a simple way of working out the shipping method by giving each product a shipping band, is a rough way of doing it but would do the job. Shipping bands A-F >>A) value = 8 result Can fit 4 to a TNT/DHL parcel >>B) value = 6 result Can fit 3 to a TNT/DHL parcel >>C) Value = 4 result Can fit 2 to a TNT/DHL parcel >>D) Value = 2 result Can fit 1 to a TNT/DHL parcel >>E) Value = 50 result Small Van >>F) Value = 500 Large Van 2 man Job. If total is less than 49 = TNT available If total is less than 499 = Small Van Available If total is less than 5000000000+ Large Van only I would like the customer to be presented with all available shipping options for their purchase so they could choose to upgrade if they wanted. An example order would be: 4 chairs in shipping band C & 5 stools in shipping band B sent to post code BD19 7QT Formula (4 x 4) = 16 + (5 x 6) = 46 and 46 is less than 49 so TNT/DHL is available DHL/TNT: £30 (number of parcels will be calculated as follows = Formula total 46 divided by 8) = 5.75 rounded up to (6 boxes) Small Van: £25 (price based on location / post code) Large Van Man: £35 (price based on location / post code) Example order 2 would be: 4 chairs in shipping band C & a Table in Band E sent to BD19 Formula would be: 4x4 (chairs) + 50 (Table) = 66 & 66 is greater than 49 and less than 500 so: DHL/TNT: N/A (as the table in Band E requires a courier or large van) Courier: £25 (price based on location / post code) Large Van: £35 (price based on location / post code) Example order 3 would be: 4 chairs in band C a table in band E and a Wardrobe in band F to BD19 Formula would be: (4x4) 16 + 50 + 500 = 566 DHL/TNT: N/A (as the wardrobe in Band F requires a large van) Courier: N/A (as the wardrobe in Band F requires a large van) Large Large Van: £35 (price based on location / post code) Please let me know your thoughts.