RE is always changing and if you have only one niche then well your limited in opportunities and subject to the conditions that exist at the time for that strategy.  

I'd be looking at multiple structures. we try to build below the average new build cost in our market in Columbus Ohio which is 515,000 last year and we target land 40-50k and urban core adjacent where we get higher price per square foot. we build for clients with margin around $190 a sq ft depending on multi or single. we can get that down in our triplex it's a little higher on our single family homes because of garages and limited economies of scale. hope that helps. idk Philly but if you show me the area and styles of homes I can give you some more insights. 

But if your a W 2 and real estate is how you are planning on retiring by investing that is a completely different lifestyle and motivation and game plan. 

It gives you the flexibility kind of like a credit card that allows you to borrow a certain limit and withdraw funds as needed.

Address Your Financial ProfileBridge the Revenue Gap: Highlight your equity in the duplex and use your sale proceeds to demonstrate “skin in the game.”Partner to Compensate Experience: A financially strong and experienced partner can help offset your limited track record.Focus on the Land Deal: Secure the land at a good price, as it’s a crucial step in gaining credibility and attracting partners.Final ThoughtsYou’re entering an exciting and impactful space in real estate development.

Under the PAL limitation, only passive losses can offset passive income.

Most institutions have a 70% limit. 

To scale successfully you have to get past the point where your newly increased expenditures exceed your increased revenue; past the point where your ROI allows you to “break even” on your investment, and past the point where the ROI is worth the increased risk, the increased aggravation, time, and “lifestyle” change, and past the point where you can step back from “operations” and concentrate on management.  

And I was greatly relieved when the three year statute of limitations had expired.  

One of the major driving factors for increased premiums is the carrier's requirement for higher replacement cost limits on file for buildings.