What We Do!

A picture of the jsl company logo.
A picture of the jsl company logo.

We provide cost analysis and estimating services to assess the value of claims.

Consultations Available at Any Stage of Building Project:

  • Planning and permitting
  • Construction projects
  • Structural feasibility
  • Contractor oversight
  • Review construction contracts
  • Cost reports
  • Mediations
  • Expert witness
  • Trial experience
  • Reasonable costs

Please consider us for your construction issues. We are here to help navigate the sometimes complex situations construction projects may have.

  • References Available upon request
  • Serving Northeast Florida
  • Call for out of area projects

Call or Text 904.309.3045

Who We Are!

A picture of the jsl company logo.

John K. Leynes, Contractor CEO

John K. Leynes, a sixth-generation Jacksonville native, is a proud graduate of the University of Kentucky and holds licenses as both a Florida General Contractor and a Florida Roofing Contractor.
John’s passion for construction in Jacksonville runs deep, rooted in his early experiences helping his family restore historic homes and commercial buildings. These formative years instilled a lifelong appreciation for craftsmanship and the preservation of Jacksonville’s architectural heritage.
Whether serving as a construction consultant or builder, John is dedicated to delivering projects that meet your expectations with professionalism and minimal hassle. His expertise spans a wide range of construction knowledge, and he approaches every project with the same commitment to honest and fair service.
John thrives on the diversity of projects and the people he works with, from consultations to full-scale building endeavors. He takes great pride in helping clients solve disputes with creative approaches ensuring the process is as stress-free as possible.
John looks forward to the opportunity to discuss your project and how he can help you.