Review and Change Website Terms and Conditions

I own a website which collects information on salary and job titles and targets individuals with job-specific information. I am now looking to sell the company to a recruitment consultancy but need to check the legalities of doing this.

The two issues that need checking are;

1) Once the company is taken over by another, that individuals can be contacted with job-relevant information by the new owner.

2) I need someone to have a review of my T&Cs. Essentially people have the option to opt out of promotional e-mails, but I want to be able to contact people with relevant information based on what individuals have provided us.