I'm a custom designer/builder with a two year scheduling lead. It is becoming more and more challenging to give prices that are meaningful two years in advance.
For most of the 90s and even into this decade, prices of materials and labor didn't fluctuate much outside a narrow range. For the last three years, though, that range has been getting wider and wider.
You can go to http://www.inflationdata.com to check the annual inflation rate going back several years then estimate what you think inflation will do over the next two years. You can also caluclate what a dollar today will be worth two years from now. You may also want to check the average cost increase of building materials over a ten year period. The downside to this is you cannot perdict shortages or economic factors that may cause a spike in prices. Ex: hurricanes or cement shortage.
