Adding a suite or making improvements to your home can bring up home value greatly if done properly and legally.  Building supplies and proper construction may be what everyone thinks is the number 1 most important thing to consider but properly obtaining a permit for the work is far more important.  
Building Permits
If a home is found without building permits the city may require that the walls or full renovation be removed to allow for proper inspection.  Make sure you are aware of any permits needed before you start working otherwise you may be wasting your time and money.  Also make sure that if you are adding a suite to your home to have it registered with the city. Most city’s have bylaws and if you are found with an unregistered suite it could cost you in municipal fines. Recently in Surrey the city has vowed to crack down on illegal suites that do not have proper registration by fining violators $1,000.
 
Building Permits
However if you are thinking of buying a home that has had work completed without a permit all is not lost.  You can request a permit for work already completed or reflect this potential issue in your offer.  When looking at home that has had recent renovations always ensure they have the proper permits and verify with the city as well.