Travel plan at the time of filing of H1B visa and converting visa from H4 to H1

[isha123]

I am currently on H4 visa and wanted to apply for H1B this fiscal year 2014. I am travelling outside us in last week of march for a month. I have been talking to many consulting comapny who can file my H1B visa, but they said if I am not present in USA at the time of filing H1B, my visa gets approved with consulate processing..is that true?
later on, when i will come on H4, after my vacation gets over, they will apply for COS from consulate processing..what is this process? does it involve lot of money ?

please help ..this is really urgent