An inflatable water slide is a fun addition to any summer party, but you must manage many planning decisions to ensure a safe and enjoyable experience. When choosing a water slide rental, some considerations need special attention. Sizing Your Inflatable Water Slide Rental The first factor you will need to assess when renting an inflatable water slide is its size. Choosing a water slide that is too large for the event area can cause safety concerns, and it will not allow enough space for the other activities you want at the event.