Received Sponsor license need some serious advice pls...

I have got sponsors license i have been working here from last 8 months as a Sales engineer.i have not taken CoS till now as i am getting confused about the designation.
i am getting confused in which category to apply whether in shortage or a normal one as for shortage occupancy there is less fee.
which visa to apply upto three year or over three years.
i have done mechanical engineering With MBA.
need some serious suggestion please.......

thanks
ur suggestions will be highly appreciated

You need to look at the SOC code for the Job type. Check if the job description falls under the Shortage occupation.
If your Job falls under the shortage occupation, then RLMT is exempted and you can apply for the Shortage occupation visa.
3 year or 5 year visa depends on the start date and end date your employer wish to provide in the COS.
If they put in a date upto 5 years, you can opt for the 5 year visa.

If your Job type does not fall into shortage occupation list, your employer will have to conduct a RLMT before a cos can be assigned to you, unless you are switching from PSW.
Again the duration of employment will determine the 3 year / 5 year visa.