Although the prospect of recording your own records may seem attractive there are many drawbacks and pitfalls you're likely to fall into. Professional recording engineers spend years, and in some cases decades, honing their craft and learning to deliver quality products that make bands happy and adhere to broadcast standards. If you don't fall into this category you may want to reconsider recording your band's next record.
I've witnessed countless bands attempt to tackle this feat on their own. Recording music can be an emotional experience, as it should be, but, imagine if that emotion is anger and frustration instead of exhilaration. In my experience nine out of ten bands that take this task on spend the better part of a year working on a record which would take a month at most and appeal to a larger audience if the job were entrusted to a professional. Before long tensions begin to run high. This often leads to arguments and ultimately the band breaking up having never sold the first record.
Additionally, getting someone who has been in the industry for many years involved and invested in your music and success can lead to them exposing your music to people you simply don't have access to. Also, having a pair of highly trained ears and expertise working on your record can do nothing but compliment your already polished sound. Finally, you wouldn't build your own house or your own car. You're a musician and it is your job to write and perform music and anything that takes your time away from that is doing you a disservice. The fact of the matter is that there are many reasons successful bands rely on someone else to do the dirty work of making records.