About Build Capital

Independent by design.
Focused by obligation.

Build Capital was established on a simple conviction: durable wealth benefits from deliberate structure, disciplined oversight, and long-term alignment. As financial complexity grows, the need for independent guidance becomes increasingly important.

Steven Castro, Founder of Build Capital

Steven Castro

Founder & Independent Fiduciary Advisor

Founded by Steven Castro

More than two decades of experience.

I've spent more than two decades in wealth management, including years at Merrill Lynch and UBS — inside the largest firms in the industry. That experience taught me a great deal about markets, portfolios, and planning. It also taught me something about how advice gets shaped by the environment it's delivered in.

I founded Build Capital because I believe advice works best when it's structured around one thing: the client's interest. No proprietary products. No sales quotas. No pressure to fit your life into a model. Just independent, fiduciary guidance — with your assets held in your name at Altruist, an independent custodian, never with me.

I work with a deliberately small number of professionals, business owners, and families in Phoenix and beyond. Small on purpose: every client gets my direct attention, not a team member's, and every portfolio gets reviewed by the person whose name is on the door.

If you've spent decades building your wealth, you deserve to know — with confidence — that your strategy still fits the life you're living today. That's the conversation I'd welcome having with you.

Fiduciary Responsibility

Aligned with one interest. Yours.

Build Capital operates as a fiduciary advisory firm. Advice is provided in the client's best interest, without proprietary products, sales quotas, or competing incentives.

A Focused Advisory Practice

Depth over volume.

Build Capital intentionally maintains a focused advisory practice so each relationship receives meaningful attention and ongoing oversight.

This includes coordination with tax professionals, estate attorneys, and other advisors when appropriate.

Investment decisions rarely exist in isolation. Durable outcomes often depend on how well the broader financial structure works together.

Begin the Conversation

Aligned with one interest. Yours.

Request a Private Introductory Conversation

Phoenix, Arizona · Virtual meetings available

© 2026 Build Capital. All rights reserved.Privacy Policy

Investment advisory services are offered through EXOS, a Registered Investment Adviser. EXOS and Build Capital are unaffiliated entities. Build Capital is not affiliated with or endorsed by any government agency. This website is for informational purposes only and should not be construed as personalized investment, tax, legal, accounting, or estate-planning advice. Build Capital does not provide tax or legal advice and does not draft legal documents. Clients should consult their attorney, CPA, or other qualified professional regarding their individual circumstances.

Investing involves risk, including the possible loss of principal. No investment strategy, asset allocation, or planning approach can ensure a profit, protect against loss, or guarantee future results. Past performance is not indicative of future results. Investment advisory services are provided in accordance with a fiduciary duty of care and loyalty, including the obligation to act in a client's best interest and disclose material conflicts of interest. Additional information, including services, fees, and potential conflicts of interest, is available in the firm's Form ADV Part 2A and Form CRS.

Client assets remain in the client's name and are held with an independent third-party custodian. Build Capital does not take custody of client assets. Build Capital coordinates with clients' attorneys, CPAs, tax professionals, and other advisers as appropriate, but does not replace those professionals or provide services outside the scope of investment advisory guidance.