Limited Company Director - Shengen Visa for business

Hello,

I'm a director of a Limited Company and I've started working with my 1st client since 01Apr2022. The client would like me to travel to Spain in 4 weeks time for business and would be reimbursing all expenses.
I have an ILR here in UK, with an Indian passport.

Referring to https://uk.blsspainvisa.com/manchester/ ... siness.php
I had the following questions. Since I have 4 weeks left to travel, I would like to get my visa processed at the earliest. It would be great if you could help me.

1. Employment Letter vs Accountant's letter: Since I am self employed, and I'm a director, does my company or my client's company need to provide this Employment Letter? OR is Accountant's letter sufficient?
2. Accountant's letter: Since I have started my business in April 2022, I am yet to receive my 1st payment from my client. Also, no VAT or Corporation taxes paid yet. What should my accountant's letter state?
3. Bank Statements: Since I have not had a pay for the last 3 months, would the consulate check for a regular income coming in for the last 3 months in the bank statements? OR if I have a minimum balance of £800 (for less than 9 days) is it sufficient?
4. Sponsorship Letter: Do I need a sponsorship letter since my client will be paying all expenses? If my bank account balance is sufficient for justifying my funds/expenses, could I prefer to avoid this since it'll save some time for me?

Thanks in advance for your support!

Hello Experts,

Could someone kindly help answering my questions? I'm cutting close on time.

Thanks in advance!