You have to determine what you're getting into. You have to know as much as possible how real estate works. That means having a good understanding of federal and state real estate laws, tax laws, managing the property, how sales, leases and financing work, and some knowledge about construction. if I could be of any assistance, please let me know.
Have you try using the internet to feed your mind regarding real estate? This will also help. Attending seminars and listening to gurus will also do.
I always recommend to new investors to write down what they want. You said you want to buy a property within the next 18 months. Write down that as your goal, then write down the step you'll need to take just before you reach your goal. Then the step you need to take just before that etc... Basically you'll be creating a road map to reach your goals. I do this right down to a daily schedule, it keeps me on task.
Before I go I have to ask if that is your goal or is your goal a much broader goal like freedom? Let me know, I also generally tell new folks to investing to start wholesaling at least 10 properties before buying and holding or fix & flipping. I have created a free wholesaling road map on my web site, it's on the front page & you don't even have to enter your name & email address.