Filing a civil case to claim money invested with a restaurant owner

We (12 persons) have invested in a Japanese restaurant (AED 100,000), each with 3 years contract.

After 2 years, the owner failed to pay the shop rent for the past 6 months and the landlord had closed the shop.

The owner signed a waiver to the landlord that he no longer has a claim on that shop, meaning to say, he already hands over the full restaurant to the landlord.

The landlord already sold the shop to another person. 3 of the investors already have bounced cheques while mine will expire in Oct 2018, and others as well.

Question 1.

What is the procedure for filing a case against the previous owner since he breached our contracts?

Question 2.

My cheque is still not due, can I file a case against him?

Question 3,

Do we need to get a lawyer with regards to our case?

Best regards,

Lea