Despite my prior budget claims, things worked out for me, and I was able to get all the electronics ordered for the laptop. Since I went with the primarily module-based design. Not much work was needed to make it work. All I had to do was solder the switches to the boost converter modules, change the plug on the solar panel, solder wires between the solar management module and the boost converter, and rig up the usb A to dual uB cable. Took maybe an hour.
Since I am going to the Hackaday DC meetup tonight, I wanted to bring it with me. However, it was just a pile of wires and stuff, not exactly transportable. Luckily, the box that the screen came in was large enough to attach the solar panel and screen to the lid and contain everything else inside. It looks a bit janky; everything is attached with twisted wire, but it will work until I can design and 3D print a proper case for it.
I went to test the AVR flashing, and found that one of the pins I had setup as part of the programmer on the pi was previously occupied. Fortunately, all I had to do was change the pin until I found one not occupied and it works great.