Tier 2 General Dependent Application within UK

Hi All,

I am going to change my visa category from Tier2 ICT to Tier2 General dependent on my wife's visa soon.
I am going for Premium services in Croydan, have some questions here:

1. Does my wife need to go with me on appointment day to Visa center as she is my main applicant? I am going to be dependent on her.
2. About IHS charges, she got visa for slightly higher than 3 years and when I check online for how much IHS I have to pay its showing 700 GBP. But I checked with a solicitor he said I have to pay 600 GBP, whom to trust?
3. Do I need to show funds in my wife's account only or in my account as well? Whose bank statements will be attached or required?
4. About application question, there are some questions in application. I have doubt about these:

4.1 Has Mrs <spouse name>'s sponsor agreed to certify your maintenance?
I have answered No here, as we are going on our own. Is this right?

4.2 Is Mrs <spouse name>'s work in a shortage occupation? what and how to answer? I have answered No here. She is Software Eng.

Thanks in Advance,
RM

Can anyone please help? Thanks