Are restaurants or real estate agents good niches for my agency?

Both are usually harder niches. Many restaurants have thin margins and a lower average order value, so you often need a lower price point. There are exceptions, for example when you already have a relationship with local restaurants.

Real estate can also be tough unless you already have a network or a strong strategy. Many agents work for a large brokerage and do not control their own website, so they cannot add a chat widget or change the phone number, and much of what you would want to do is not possible. Look for agents who work independently and control their own site.