In Houston, you can either invest locally or explore strong Texas markets like San Antonio (affordable duplexes, strong job market), DFW suburbs (duplex-friendly zoning, growing economy), or Houston suburbs (Spring, Cypress, The Woodlands for good schools and tenant demand).

Not my idea, this is from RichDad, but really good advice.I would suggest to do that on the side and think about a W2 job.

I've painted more walls, ceilings and trim work than I could ever count in my lifetime and *I* suck compared to professional painters, and most of my paint jobs could pass for lower-end professional jobs. 

Stable job for 20+ years.

That can be a draw back if the market is on a mad run up tho.Also, I would always have enough in a heloc to cover your 401k loan in the event of job loss or if you quit your job. 

Nice job!

Also, focus on 2 years of job/income stability.Class D Properties:Cashflow vs Appreciation: Typically, all cashflow with little, maybe even negative, relative rent & value appreciationVacancy Est: 20%+ should be used to cover nonpayment, evictions & damages.Tenant Pool: majority will have FICO scores under 560 (almost 30% probability of default), little to no good tradelines, lots of collections & chargeoffs, recent evictions.

Over this time I have acquired my contractor team and have vetted them through my job as a property manager, figured out my strategy(Off Market/Deep buying) and location.

Real estate is a long-term game, and your patience will pay off.Since you’re a dentist, you may have a busy schedule, so consider working with a good property manager.

.- If you hold a rental until death, you can pass it on with a stepped-up cost basis, limiting captial gains if then sold (limited by inheritance tax limitations).Too many newbies on this site trying to replace their day job income via "passive" real estate investing w/o digging deep enough to understand how it really works.