Lots of tremendous tips in this thread. I have been a Realtor for 27 years and still learning something new everyday. It's a great profession.
I will say that in some ways this gets easier with time. I no longer need to aggressively prospect for new clients as over 85% of my business is past clients and referrals. How did that happen? I would like to think by following the strategy of one of the writers above - giving each transaction more priority and attention than if it were your own. I have always thought that by providing superior service, the money will follow.
As to who to prospect to build your career? Well the traditional advice is "list to live." Nothing wrong with that but when I started I took the long view. Sure I wanted listings but I wanted people who would use me again and again over their lifetime. Who were those groups? First time buyers and investors.
First time buyers are typically younger and have decades of life changing events ahead of them like marriage, children, job changes and sometimes, sadly, divorce. Almost all require a residence change. Older buyers getting into the "dream house" tend to stay for a bit.
Of course we are here because we love real estate investing. And what investor do you know that has done 1 deal and quit? They are some of the best clients for Realtors yet you will find not many Realtors actively work this niche.
I got into the investing game late. But I will tell you that one reason I did is that I saw what some of my clients were doing and I hit myself in the head for not doing it myself. So many of the clients I helped had built portfolios that provided enough cash flow that they could choose not to work or do whatever type of work they wanted.
As a Realtor working with investors you are not only generating income but getting an education as well. For me it took forever to learn the lesson that real estate is a path to financial freedom. And I am still learning new tricks and ideas from my investor clients.
I can think of nothing else I would rather do. Okay - professional baseball player but that ain't happening in my 50s.