By Nav Athwal, founder and CEO of RealtyShares.

From an entrepreneurial perspective, there are certain foundational elements that are necessary for breathing life into a startup. Time, money, determination and a brilliant concept rank at the top of the list, but there's something else that can prove critical to a founder's long-term success: the strength and quality of their network.

As a founder and CEO, I've experienced the various growing pains associated with building a company from the ground up. One of the things that's helped get me to where I am today is the extensive network of mentors and advisors I've connected with along the way.

Measuring the Value That Mentors and Advisors Bring

As a founder, there's a tendency to assume that your grit and hard work are sufficient to drive the success of your startup. While these things can take you far, they're not a substitute for the experiential knowledge that comes from heading up an established company.

That's what makes mentors and advisors such a crucial part of the equation for startups. Surrounding yourself with the right people -- at the right time -- can be instrumental as you grow and begin to move toward long-term sustainability.

Our advisory board's experience with growth has been an excellent resource for us as we've scaled our company. The type of mentors and advisors that founders should associate themselves with is linked to what stage their business is in. In the early days, you might have one set of advisors that helps you find your footing, and as you move onto the next phase of growth, the people you look to for advice and insight will in turn evolve.

Ultimately, however, the emphasis is the same: Form relationships with people who have been there, done that, and are positioned to help you bust down the doors that need to be opened so you can realize your company's vision.

The benefits of a mentoring or advisory relationship aren't one-sided, either. For the mentor or advisor in question, there's often an ingrained desire to pay it forward in the form of sharing what they've learned over the years with an up-and-coming entrepreneur.

There's also a financial component at work, in that many advisors have the ability to tap into the equity of the company they're helping, which can be lucrative if the business proves successful. Finally, mentors and advisors have an opportunity to expand their own networks as they work with new founders.

Building Your Network as a Founder

My best advice to founders who are seeking to recruit advisors and mentors to join their network is simple: Start with the network you have. Take an inventory of who's already in it. Then, look at who they're connected to, and ask for introductions. If you feel that your network is lacking, reach out to other founders to put the wheels in motion.

Even when founders are in different industries, they're often dealing with the same difficulties, issues and challenges when it comes to reaching their growth goals. If you don't have any founders in your network, joining an incubator can help you meet and share resources with other like-minded entrepreneurs. Your investors can also offer to make introductions if they've worked with other founders before.

In some cases, an advisor may even become an investor themselves. That was the case with our angel investor -- a founder in his own right. He was very passionate about our concept and what we were doing, and his mentorship has proven invaluable as we've forged our path.

The internet is another potential wellspring for making connections. I've started countless conversations with seasoned entrepreneurs who fit the advisor or mentor mold through LinkedIn or AngelList.

Ultimately, it comes down to leaving no stone unturned. The more that goes into developing and nurturing these relationships, the more likely your network -- and startup -- will thrive.

Nav Athwal is the founder and CEO of RealtyShares, an online curated marketplace for real estate investing.