EDIT: This sounded condescending when I read through it. It's not meant to be. Just advice from someone who's overdone things in the past :)
It depends what you're building. Don't over do it if it's a small site with local coverage.
Do you really need 180 currencies, shipping to 196 countries, discounts, coupons, recurring payments and the "kitchen sink"?
If you really do, then it's probably a big job and worth a proper feasibility study, rather than a forum post. :)
Or does the client just have unrealistic aspirations? Sometimes you've got to be realistic. Most ideas are NOT the next big thing.
On the other hand, if it's your local plumber or restaurant, you can easily create a very light shopping cart and payment system in short order with Laravel. One that you know inside out - and doesn't require infinite resources to run it.
EDIT:
By the way, I don't know what you have against OpenCart, but many moons ago when I did that type of work, OpenCart was much easier to work with, more stable and ran on much lesser hardware than Magento. I don't really care what the architecture was, at the time it just worked and with very few problems. Maybe things have changed.