When remodeling or updating your home, a smart homeowner will consider the ROI or return on investment. This means "if" you make an improvement how much can you expect to recoop on resale.  Many an overpriced home is listed on the market by sellers who think they will recoop 100% of all improvements which is not the case.  The below article shows the reflection of research done nationally on the ROI for some of the most popular improvements.  Year after year a front door is always 100%+ ROI

http://www.houselogic.com/photos/home-improvement/best-home-improvement/slide/steel-entry-door/

I always encourage homeowners to make improvements they will enjoy in the short term but to keep the long term in mind if they should sell in the future.  It is always important to remember to not UNDER improve a home as well.  If many homes in your neighborhood have hardwood floors for instance and you put in an inexpensive laminate to replace your carpet - it will diminish its value in the eyes of buyers.  Not sure what to do?  Contact a Realtor in addittion to your contractor before you remodel.