Somewhere between those two extremes are some other great options to consider, including wall air conditioners. Wall air conditioners, also known as through-the-wall or in-wall air conditioners, are designed to be a long-lasting fixture in your home. These air conditioners are mounted into a hole in the wall and are permanently attached to your house. Therefore, these systems are best if you plan on staying in the same location for a number of years and a central air system is not an option for you. It's important to note, however, that these wall AC units are only designed to help keep one room, or perhaps two at most, comfortable during warm seasons. They cost less than a central air conditioning system but also offer less coverage.
The most distinguishing element between wall air conditioners and other wall AC units is their permanence. Installation costs of wall units can be quite high, though not as pricy as a whole-house system. If you are looking to replace an existing wall air conditioner, the installation process is much simpler and you can install one of these units yourself. However, if you are not replacing an existing unit, you have to cut a hole through a wall, which can be expensive or time-intensive. If you are not comfortable cutting a hole in the wall yourself, you should look for a local contractor to help you install the unit.