You’ve done the work.
Now you need a partner who can drive it forward.
That's where we come in.
We treat capital like the critical lever it is, a tool to get your deal across the finish line. We underwrite like investors, communicate like operators, and negotiate like we’re on the hook for the outcome.
More about us:
We are a boutique commercial mortgage brokerage built for real estate investors and developers.
Founded in Chicago, with deep Midwest roots and national reach.
Experienced in structuring complex deals across multifamily, office, industrial, retail, healthcare, and mixed-use.
We underwrite every opportunity with a focus on real-world fit and long-term value.
Our role: make sure the deal works, the numbers hold, and the structure supports your strategy.
Alex Mermelstein
Managing Partner
I’ve spent my career on all sides of the table: broker, buyer, and borrower.
That experience is what Marblestone Capital was built on. I started at Marcus & Millichap selling NNN assets nationwide, then moved into property management for a Chicago-based owner-operator. From there, I underwrote multifamily deals at a private equity firm, learning to see real estate through a developer’s lens. Most recently, I served as Senior Underwriter at a national brokerage platform.
Along the way, I built my own portfolio, flipping properties, funding gut renovations, and refinancing with local banks. Some deals were wins, others were lessons, but all of them shaped how I approach risk, timelines, and financing. Marblestone was launched to bring that full-circle perspective to every deal.
How We Operate
Integrity
We’ll tell you when a deal doesn’t make sense, even if it means not moving forward.
We’ll tell you when a deal doesn’t make sense, even if it means not moving forward.
Experience
We think like buyers, so our structures hold up.
We think like buyers, so our structures hold up.
Partnership
We care about long-term outcomes, not short-term commissions.
We care about long-term outcomes, not short-term commissions.
Transparency
You’ll know where things stand, which lenders we’re talking to, and what happens next.
You’ll know where things stand, which lenders we’re talking to, and what happens next.
Results
We only win when your deal closes, so we do what it takes to get it there.
We only win when your deal closes, so we do what it takes to get it there.
How We Operate
Integrity
We’ll tell you when a deal doesn’t make sense, even if it means not moving forward.
Experience
We think like buyers, so our structures hold up.
Partnership
We care about long-term outcomes, not short-term commissions.
Transparency
You’ll know where things stand, which lenders we’re talking to, and what happens next.
Results
We only win when your deal closes, so we do what it takes to get it there.