Team | Corbel Partners

How the partnership formed

Thirty-five years of working in the same market

Corbel Partners was formed in 2026. The relationships behind it are considerably older. Roles below are stated as held at the time.

1990s

Joel Flachs and Mark Phillips meet at Colliers L&A

Joel as Director of the Investment Services Group; Mark as a Senior Sales Associate over eleven years with the firm, having opened its first Lehigh Valley satellite office in 1990.

Brokerage

2000

Joel's first syndication, 2600 Beltline Avenue

Sponsorship

2005

J&R Investments created

Joel founds the firm to acquire and actively manage commercial real estate across the Mid-Atlantic.

Sponsorship

2010

Total investments reach $100 million

Sponsorship

2015

Mark launches two GSA funds

Through a partnership he created, the funds secured over $70 million in properties leased to the federal government.

Sponsorship

2015

Alisha Mancinelli joins to lead finance and investor operations

Accounting, reporting, treasury, partnership administration and investor communications across the portfolio.

Finance & investor operations

2018–2020

Joel and Mark partner with Rose Rock Development on two tax-credit conversions

Office buildings converted to apartments in Tulsa, Oklahoma.

Development

2019–2025

Joel and Mark partner on $60 million in self-storage projects nationally

Development

2026

Corbel Partners formed

Joel and Mark partner with William Fink and Alisha Mancinelli on a new venture acquiring veterinary, medical and industrial buildings, typically between $750,000 and $3 million.

This venture

Principals

The people

Joel Flachs

General Partner

Founder and Managing Partner of J&R Investments since 2005, serving as general partner across a Mid-Atlantic portfolio of office, retail, industrial and multifamily assets. Previously Director of the Investment Services Group at Colliers L&A and Chairman of Bala Properties Group. Licensed broker in Pennsylvania and New Jersey and a Pennsylvania broker-appraiser. Three decades of ownership and brokerage in the same submarkets give the firm direct access to sellers, lenders and brokers across the region, much of it ahead of a marketed process.

Mark Phillips, CCIM, SIOR

General Partner

Since 1978, Mark Phillips has been building up an impressive body of work in real estate with experiences that span construction, development, investment, and over 40 years in commercial real estate brokerage. Mark has also been involved in multiple real estate private equity syndications, including ground-up developments and multifamily projects. His feats include the creation of a powerful partnership that resulted in two funds which secured over $70M in properties leased to the federal government. Today, Mark is as industrious as ever – he recently concluded over $100M in development projects through various partnerships, including six Self-Storage projects and two historic tax credit multifamily conversions.

William Fink

General Partner

Commercial tenant-representation broker specializing in medical and education users, executing over $30 million in annual transaction volume for operators including publicly traded, credit-backed tenants. Fifteen years across brokerage, acquisitions and new-construction operations, with principal experience as an investor in industrial, office, private-lending and development assets in the US and UK.

Alisha Mancinelli

General Partner

Director of Finance and Investor Relations at J&R Investments since 2015, responsible for accounting, reporting, treasury, partnership administration and investor communications. Previously PricewaterhouseCoopers, David's Bridal and Wawa. BS Accounting, MS Marketing, Saint Joseph's University.