Unless you're familiar with all that's involved, the most straightforward way would be find a contractor or two who can give you an estimate. You could tell them that there are some parts of the job you may do yourself (e.g. kitchen cabinets or whatever), and have them list those separately to get a sense of how much that might save you. They may also have good insights about relocating/opening up walls, kitchen redesign, etc.
If you want a sense of the factors involved in estimating costs, have a look at
this spreadsheet or the
web page it comes from.
If doing kitchen cabinets and granite, you can save a ton of money if you find one of the Chinese business that import prefabbed granite and no-brand cabinets (about 1/2 the price of comparable Ikea cabinets, and 1/3 the price of other granite installed) directly from China. See, for example
http://gscabinetandgranite.com/ in Seattle - there are a ton of these places in Seattle, and I've heard they are in other metro areas as well. If I recall, the shop we used a couple years ago sold their basic common granite, as a 16 square foot, prefinished slab for under $200 with nominal install fees. The guy who helped with our design was an online gamer in his spare time... It was pretty impressive seeing how fast he could drag/drop and reconfigure all the various options into place in his 3D design software.
