Jorge,
Welcome to automotive scope diagnostics.
It is often said that you need a 'starter scope' as a beginner and then upgrade later to a better one. I have never understood this. Seems a waste of time and money to me.
No matter what you get, you will need to invest some time to learn to operate it. If you plan on getting serious about scope work, then why not cut your teeth on the best. Then you only have to buy it once and the time invested will be better spent. You can learn some bad habits with a lesser piece of equipment that will then have to be unlearned.
PicoScope is the most powerful automotive scope available.
Can you tell me if i'm going to need more diagnostics leads or something else that does'nt come with this package for example diagnostic 3 or more sensors at the same time.
My advise would be to get the complete four channel kit and, add to that the other things you want. The complete four channel kit will have everything you need to get started. Other things needed depend on the vehicles you work on most often
Be sure to also check out the free addon..Pico Diagnostics:
http://www.picotech.com/auto/pico-diagnostics.html
Pico direct support is great. You may also want to research a distributor that can supplement that with more automotive specific in depth support and training.
Tom Roberts
(The Picotologist)
http://www.autonerdz.com
skype: autonerdz
THE PicoScope Automotive Authority
In North America