I will add that there are some considerations that come to mind. If you can afford it, go with a siding that's at least .040 or more in thickness. It 'moves' less in extreme temperatures, thus, minimizing buckling and pull-outs. Also, buy an extra box, perhaps some extra channeling and so on, in case later on you need some replacement material. Or, maybe you'll install a window or something. Over a number of years, mfgrs. tend to change style and material composition. Of course, your wife wants EVERYTHING to match.
Be sure you check that your contractor is at least Bonded and Insured. And if you can, when you've chosen your siding, get a copy of the Warranty to be sure that what he's gonna do is covered in the warranty. (For example, most warranties require a smooth mounting surface.)
And lastly, if you have any particualar questions that you need answering, you know where to find us. My best to ya and hope this helps.
Jay J -Moderator
PS: Consider adding an electrical outlet (or 2) and additional hose bibs on the sides of the house that don't have them now BUT would be useful if they did. Now is the time. At worst, you could have the Contractor install the electrical and hose 'accessory block' in the location you want, and later on you can do the plumbing and wiring. Be sure you have 'access' INSIDE the hose where you end up putting the block. Visit Builder's Edge, click Product Catalogue, click Finishing Accessories (on the picture) for a sample list of Accessories. You'll see quite a few.