To add a couple more comments...
A two layer stackup is much easier to reproduce unless they're using exotic substrates, but make sure you use the correct substrate thickness, they're often thinner than 1.6mm! If it says 1mm, you must use 1mm! Double sided also usually means that the transmission lines are wider due to the increased dielectric distance to the ground plane.
The problem of using thinner boards is that the physical strength of the board reduces, so care needs to be taken to avoid flexing of the board or your MLCC caps will crack over time, and during assembly the board may flex risking associated connection problems. I did a CC3200 prototype board a few weeks ago on 0.4mm board, it worked well except that for a production design it would be difficult to make rigid enough.
I have started to use Murata MM8030-2610RJ3 RF switch/jacks as a matter of course on prototype RF boards, these are miniature RF sockets rated to 11GHz with passthrough when nothing's plugged in to them. This means you can easily probe in circuit with your VNA. They're reasonably cheap too, $0.20 in qty 1ku. For production, you can replace with a colocated 0402 0R or MLCC cap. I will admit that the probe adapters aren't very cheap though!