My concerns would be overbuilding and first-time homebuyers' ability to qualify for financing......which could very well lead to looser underwriting  guidelines.   

If you have the ability to house hack 3-5 properties in the span of 5 years, that's an excellent way of building wealth!

Key metrics include# of assetsAsset typesRisk ProfileDate of acquisitionsTotal CapitalizationTotal EquityTotal DebtSponsor GP shareSponsor Role# of exitsRealized IRRs, EMsSponsors with a consistent track record of delivering projects on time and within budget are more likely to execute future projects successfully.Risk AssessmentIdentify and evaluate potential risks associated with the sponsor's ability to execute the project successfully.

A desire and ability to share their knowledge4.

Build the confidence of your abilities by having that real life experience.

Fear will kill your ability to grow, so why let it? 

Moving to a self directed 401k I would lose the ability to withdraw for 8 years. 

The main pro for building would be the ability to control where I live while living in the house, whereas most multifamily homes are within city limits and not my preferred choice of dwelling. 

In my experience the basics for a functional RE based CRM are:Custom Fields for Data Objects (Leads, Prospects, Applications, Buildings, Units, etc...)A Screening Engine (background/credit checks, employment verification, etc)Online Rental Application (this should automatically run the application through screening)Ability to mass email/sms leads and tenants to provide informationSurveys/Inspection formsI've been building real estate CRM tools for years.

The multi unit works better for financing due to ability to use rent from the other unit to meet income requirements on the loan.