If you are just starting the main focus should be a full body workout. While a gym with all the latest equipment is nice you don't have to start out that way. There are some really great dvd's and other resources on the internet.
The other thing that a good boxing routine dvd has is interval training. This is extremely important to increase the fat burn. You will lose weight much quicker.
A of people don't have the money to pay the monthly fee for a gym. Many of them are very nice and fun to be at. Sometimes, being around other folks helps in the motivation department.
The best way to start out is with a full body workout at least twice per week on non-consecutive days. Mix in your other exercise routines and see how things go.
There are always pros and cons to anything. A boxing training routine isn't any different. You just have to be careful about the ones that you buy.
One thing that you may want to consider is the qualifications of the instructor. How long have they been doing this? Did they develop the routine on their own or hijack bits and pieces of it from other folks?
Is there a money back guarantee if you aren't happy with the product?
Don't be surprised if you don't see any increases in muscle mass right away. It does take a little! You should definitely see some other things happening though. We all sleep better at night when we are active. This is something that you should notice right away.
Your energy level should improve also. When our hearts and lungs are working at their desired capacity we just feel better. This is where boxing workouts at home really begin to make a difference.
As time goes on the routine should becoming more challenging. If it doesn't seem like that is the way the workout is set up you may want to buy another dvd.
Sometimes the best way to try things is to just do it!