The first and most important thing you should look at is the age
recommendation, if the swing is recommended for a child older than
yours, you shouldn't get it. Also make sure that the materials will
not rot, splinter, rust or otherwise go bad. If you are buying a
prepackage set, this is not likely much of a problem, but still
something to consider. Finally, make sure you have enough room for
the swing and that the area can be covered with soft gravel, grass
or rubber. The majority of accidents are caused by inappropriate
materials, so this is very important.