Granite is a beautiful stone as well as being one of the hardest of the natural stone surfaces. Unlike its plastic counterparts, or the composite counters, granite offers superior heat resistance. This makes it great for countertop surfaces. Naturally resistant to acid, granite surfaces rarely etch (there are a few calcite containing granites that will etch in the presence of acidic spills, cleaners or fruit but this is rare) making it an ideal counter top surface.
However, as with all natural stones, these materials are porous and therefore susceptible to absorbing discoloring spills or greases resulting in unsightly stains. While stains can technically be removed, it requires patience as it may take several 24-hr steps to successfully remove. During that time, your granite surface is out of service. Total time could range from a day to a week. As you can imagine, this can become a costly process if only due to the time associated for the multiple trips, (unless you are willing to do this yourself). This can be a costly process if it is being removed by an outside vendor. As you can imagine the cost of repair far outweighs the cost of prevention. Avoid this inconvenience and expense by simply cleaning and sealing your granite on a bi-annual schedule.
Many manufacturers now "resinate" their granite slabs as part of the manufacturing and shipping process. Resinating is the act of vacuuming a plastic resin through the slab, that will become your stone countertop. This is done to counter or offset the natural brittleness of some granites making it easier to ship. It is this process that we can credit for the dramatic increase in the number of granite types now coming to market.
A side benefit of the resinating process is that it naturally fills in the stone pores, effectively reducing the need to seal a resinated granite, saving the home owner time and money. If your granite was installed AFTER 2005 there is a good chance your granite counter is resinated. If your granite was installed before 2005, sealing it properly becomes a more critical step. Sealing it on installation is the first step in keeping your granite looking good for a long time. However harsh cleaners and acidic spills can degrade your seal over time, so it is recommended to have it re-sealed every other year.
Granite is beautiful and tough. It's a perfect kitchen counter surface. Remember, periodic sealing will help you maintain a stain resistant surface for your granite counter top so it can last you a lifetime. Properly cleaning and sealing is your key to saving money and maintaining quality long term.
Finally, when searching for a professional service company, make sure they stand by their work. Most companies will offer a free estimate for the work and if they don't, call someone else. Find out how long that company has been in business and make sure you ask plenty of questions. A good service company will have no problems answering your questions and dealing with any concerns you may have.