An un-managed dedicated server where the server is owned by the client and not the host is known as a co-location web hosting. With the difference where the server is owned by the client and not the host, such kind of hosting server would be a much cheaper hosting in a long run.
Firstly, you do not need to pay the server rental fees but you do have to cover the cost for the space where the server is located and also the power consumption as well as the bandwidth. The way web hosting company offer such kind of host is usually similar to other normal web hosting packages. They calculate the fee required based on the normal features like the amount disk space taken, the amount of data transfer and so on.
To start hosting with a co location server, you must ensure that you have a rack mountable server because it is the only type of server which is accepted by most of the web hosting providers and data centers. To be able to use co-location host, you must also possess a certain amount of skill regarding web server because the support provided for this kind of web hosting is limited. Furthermore, you will have to discuss with your web provider regarding your accessibility of your server. You have total access to your server but maybe not at all times.
Therefore, a good communication should be done with your web provider on the times you can access your server. This is important because you would have to access your server to solve problems so that it will not go on for hours and hours. If you like to have a server all to yourself, co-placement is suitable for you because it is just like a dedicated web hosting but you own the server and not the company. You will be able to get all the benefits of a dedicated server hosting and the freedom to modify the server. Finally, the cost for a co-location web hosting is much cheaper after you purchased the server.
Although the technical requirement is much higher, you will still benefit from a co-location web hosting because of the freedom and its similarity with a dedicated server hosting.