Though the questions come in to you over the phone and in person, a great many of them come in as email as well. If in person or on the phone, just make yourself a note to write a post when you have time. The question is all you need to note down, as you know the answer. If an email, it's even faster and easier. You can take their question and copy/paste it in as the blog post title. Then copy your email text that you sent as the answer, and paste it into the body of the post. You've just created great content for your real estate blog.
There is the SEO (Search Engine Optimization) aspect as well. These questions and answers will by nature include key words and phrases that will help you to increase your search engine exposure. Don't worry about re-writing the answers extensively for SEO. The whole purpose of this article is to help you to implement a fast and easy way to create new content for your blog site. This could help jump-start your blogging.
As far as mechanics, a good way to organize these FAQs is by category and then sub-category. You could have a main category of FAQs or Real Estate FAQs, then as you add enough of them, sub-categorize by subject matter. An example that should fill up fast would be a "Closing Transaction" sub-category. You answer a lot of questions about the process, so the content will build quickly. Then do a "Negotiation" sub-category and keep on creating.
Another visitor-friendly and SEO effective strategy is to link within your site from these FAQs. If you have an FAQ like "How long does it take to close a transaction?", you may have a full article about the steps involved. Answer the question with some time frame information, and link them to the other article for more information.
Your real estate blog will grow faster if you use questions and answers for content. Just go over your saved emails to find a fast start. Also, start to notice how many questions you answer every day.

