Our Team


At Mar Con Builders, we pride ourselves on a team of professionals that understand the changing dynamics of modern construction works. Creativity flows through our vein. The way we see it, every building project is unique, and no project is too small or too big. We love to think outside the box and that enables us to create designs projects and construct buildings that are the best of both worlds.

We put the best of ourselves towards maintaining the construction industry’s best practices by ensuring safety standards, fine craftsmanship, and client satisfaction.


Marco Manriquez


Accomplished, innovative general contractor who has demonstrated ability to deliver projects with exceptional results. Marco is highly motivated with solid experience managing all levels of projects. He is responsible for providing strategic leadership for the company to establish long-range goals, strategies, plans, and policies. With years of experience, from a Carpenter apprentice to a Project Manager, Marco has developed a stronghold knowledge to establish his own business in Construction.

Diligent and resourceful Project Executive poses expertise in establishing schedules and project parameters, with strong ability to contribute to strategic plans and project reviews. Andy makes sure that day-to-day operations of the company are properly executed. He also assigns responsibilities, develops functional roles and oversees operations to ensure that the company’s visions are carried out. Andy serves as the second person in command. His persistence in running the projects has manifested in the excellent quality of work the company has come to be known by. Andy has developed his skills from floor layer apprentice to a project manager for various projects. He has continued to maintain his certificates on different Flooring and Floor Covering Program Certifications to date.

Andy Arechiga

Vice President

Stephen Nerheim

Chief Financial Officer

Serving as the firm’s Chief Financial Officer, Stephen brings a wealth of knowledge and 25 years of experience in business and financial management. Stephen graduated from the University of the Pacific with a BS in Finance and Economics and went on to obtain his MBA from Pepperdine University’s Graziadio School of Business Management. Stephen’s prior experience includes executive roles in commercial construction, real estate development, retail/wholesale and retail banking. Stephen’s focus on “Excellence in Customer Service” spans every level inside and outside of the organization.

Bill is the Chief Estimator, Director of Preconstruction Services and Director of Value Engineering for MarCon Builders. Bill has over 50 years in the construction industry with the background in Nuclear Power and Industrial Plants, 30-50 story high rise and low rise structures, hospitals, research and healthcare facilities, sports facilities and stadiums, military, educational facilities from K-12 to university projects as well as commercial facilities and civic projects including performing arts centers, libraries, city halls, fire stations and governmental buildings for City, State and Federal clients. Bill has estimated, managed and overseen projects from Alaska to Puerto Rico, New York to California. Bill also has an extensive background in hi-tech and biotechnology projects.

William Lonigan

Project Director / Sr. Estimator

Rouella Alferez


Rouella is an experienced well-rounded Accounting Professional, she had managed all accounting operations. Strong business analysis skills, experience in Finance, Human Resources, Marketing, Information Systems, and Project Management. Rouella is a graduate in BS Accounting from the Golden Gate University and obtained her Master’s degree in Accountancy at the same university in 2014. On her
weekends, she serves as an auxiliary officer with the United States Naval Sea Cadet Corps, United States Navy where she is holding the billet as a Financial Officer. She continues to develop her skills as an Accountant by taking lessons at night, attending webinars to obtain CE credits. She improves her skills by taking LinkedIn Learning courses on her free time.


At Mar Con Builders, we take safety very seriously. It is our policy to provide a working environment that goes beyond typical safety standards. We want to make sure that everyone who works on our job sites is in better condition at the end of the day than when they arrived. The personal safety and health of each employee of this company is of the utmost importance. We give the prevention of accidents and injury precedence at all times.

Safety is part of our culture, and we are constantly seeking ways to improve our methods. Any workarounds that put the safety of the job site, our staff, and the surrounding community at risk is unacceptable.

Our safety code includes the following:

100% tie-off policy

Excellent communication strategies

Safety training for all employees and subcontractors

Close monitoring of subcontractors

Stringent personal protective equipment (PPE) policy