Hello everyone!  I'm writing to introduce myself: I'm Justin, and I live in Dallas, TX, arguably one of the fastest-growing markets in the US, both by population influx and real estate demand.  I came across BiggerPockets as one of the first resources I encountered when I became interested in real estate investing, starting off with the BP podcast (I've marathoned ~60 episodes in two weeks) and the site itself.

I'm excited (and to be honest, a fair bit intimidated) to get started in real estate investing, and I thought I'd reach out to the community to get more involved and accelerate my learning process.  I've done a fair bit of research over the past few weeks, reading books such as What Every Real Estate Investor Needs to Know About Cash Flow, The ABCs of Real Estate Investing, and Investing in Duplexes, Triplexes & Quads.

As I'm starting out, I'm interested in investing in single family residences and 2-4 unit multifamily for a long-term buy-and-hold strategy.  I have an initial goal of attaining $3,000 per month ($36k annually) in income derived from real estate investments in order to supplement my full-time job.

To kickstart this post, I thought I'd ask some questions to the community that I've been pondering over the course of my real estate education:

1. First, market timing: I have the sense that the Dallas market has been on the upswing for the past several years, accelerating even more rapidly since the announcement of several major companies (including Toyota) moving to Plano.  I'm concerned I'm jumping in at a time when values are high and getting higher; at the same time, I don't want to wait too long to get started in real estate investing.  What are your thoughts on whether (or to what extent) I should be concerned about buying when the market is hot?
2. A quick question on entity structure and insurance: As I'm planning on investing in multiple properties over the long-term, I'm considering forming a series LLC in Texas, which has several benefits in terms of administrative cost reduction (relative to having an LLC per property). My question is whether (or at what point) should I consider having umbrella insurance? Are there rules of thumbs governing this decision?
3. Areas to consider: For those who are familiar with the Dallas market, would you consider Plano/Allen/Frisco to be essentially tapped out?  I've spoken with several local real estate folks who have said the demand is now stretching as far as McKinney and Denton.  What areas might you recommend I start looking for deals?
4. I'm planning to cross-post this introduction to the Dallas subforum, but if anyone here reading this is from the Dallas area, please reach out!  I'm excited to meet others who share an interest and passion in real estate.

A big thanks to everyone who took the time to read this wall of text, and I look forward to hearing everyone's thoughts.  =)