Our team is experienced in all aspects of asset management acting for owners of property portfolios.
We deal with all aspects of renewals of business tenancies under the Landlord and Tenant Act 1954.
We also advise on agreements for lease, new leases, re-gears, surrenders, licenses, deeds of variation, rent deposits, authorised guarantee agreements, and landlords’ enforcement.
We work closely with colleagues in our Dispute Resolution team where property disputes arise.

Mark Cornelius

Jonathan Gross

Michael Haringman

David Quastel

Owen Walsh

Roberta Organ

Partner
Mark Cornelius
Mark joined Quastels in 2016 and deals with all aspects of non-contentious commercial property including landlord and tenant work, acquisitions and disposals, development, option agreements and secured lending. Mark’s clients range from private investors, developers and pension funds to restaurateurs, hotel operators and retailers.
Mark offers a first-class service to his clients keeping them abreast of progress throughout by clear, prompt and personable communication. His speed of response and pragmatic approach allied with his commercial awareness ensures that transactions are concluded within a client’s desired timeframe and on the best possible terms.
Email:mcornelius@quastels.com
Tel:+44 (0)20 7908 2555

Partner
Jonathan Gross
Jonathan trained and qualified as a solicitor at Allen & Overy where he spent six years before joining the real estate practice at SJ Berwin & Co. In 1998 he left SJ Berwin to join David Quastel as a founder partner of Quastels and has almost 30 years experience as a commercial real estate lawyer. Regarded by his loyal clients as a deal maker his clients rely upon him for his tactical and strategic approach to getting things done.
As legal adviser to some of the UK’s largest family offices, private companies and entrepreneurs he is respected by his clients for his depth of experience in investment, joint ventures and special situations and his ability to effect introductions at the highest level.
Jonathan has a degree in law from Trinity College, Cambridge.
Email:jgross@quastels.com
Tel:+44 (0)20 7908 2544

Partner
Michael Haringman
Michael Haringman is the firm’s Senior Partner. Michael advises primarily on commercial matters, commercial property transactions and trusts. His clients include multiple retailers whom he advises on all commercial and strategic legal aspects of their operations, including acquisitions and disposals of both businesses and real property. Michael also advises property investors in relation to their transactions, including acquisitions and disposals, developments, lettings, joint ventures and funding requirements.
Michael advises a number of overseas clients as well as UK based clients.
Michael has developed close and loyal relationships with his clients, who describe him as being “supportive, insightful” and “100% reliable and dependable”. His clients appreciate his analytical and positive approach to all situations and value the “complete peace of mind” upon which they have come to rely.
Email:mharingman@quastels.com
Tel:+44 (0)20 7908 2529

Partner
David Quastel
David Quastel is the firm’s Managing Partner and is a versatile and highly skillful commercial/property lawyer with special expertise in real estate development finance and structuring complex property related joint ventures.
David’s forte extends well beyond providing technical legal advice and clients have come to value and rely upon his hands-on strategic advice at the earliest stages of planning and structuring complicated property, corporate and international transactions.
Clients appreciate David’s strategic insights and absolute attention to detail and describe him as “a formidable negotiator”, “a unique problem solver”, “a driving force in concluding a deal satisfactorily” and a “wonderful technician”.
Email:dquastel@quastels.com
Tel:+44 (0)20 7908 2526

Partner
Owen Walsh
Owen is the co-head of the Commercial Property team. He is recognised by the Legal 500 and acts for clients in most commercial sectors, including leisure, luxury retailers, professionals, hotels, institutional and local authorities.
Owen deals with all types of commercial property transactions including sales and purchases, business tenancies, development, property finance and asset management.
Testimonials from clients include:
‘Every transaction has sailed through without a hitch, due to Owen’s impeccable attention to detail, coupled with a strong commercial understanding of the market.’
‘Owen Walsh deals with all my transactions and is always there day and night. His communication is brilliant, he is extremely thorough with research and he develops leases to suit my style.’
Email:owalsh@quastels.com
Tel:+44 (0)20 7908 2541

Senior Associate
Roberta Organ
Roberta is an experienced real estate lawyer specialising in all aspects of commercial property. Roberta advises clients on a wide range of property matters including acquisitions and disposals, landlord and tenant transactions and real estate finance. Roberta works across many commercial sectors and acts for clients in retail, leisure and hospitality as well as private investors, corporate occupiers, lenders and developers.
Roberta qualified as a solicitor in 2014 and joined Quastels as a Senior Associate in 2021.
Email:rorgan@quastels.com
Tel:+44 (0)20 7908 2542