So I've secured the last of the 305's missing parts (shell end wall). In the same deal I'm working with the seller, I get two partial 103's (mostly shell+frames, missing end-walls on one and liner for both), five rapid entry vestibules, and a "spare" 305 which will go towards the bus project (mother of all roof tents). This purchase will be done in August, so patience again...
At least one of those 103's will need a liner+floor - it will connect the two 305s to the 303 latrine tent. As a hallway, I should be able to use the side door with a custom boot for the S-250 shelter with its pop-up tent to add it to the complex is a weatherproof/"air-tight" fashion. The second 103 was just part of the deal - didn't really have an "urgent need," but once I thought of using a boot to the S-250, I realized that my bus project might also need a hallway to add it to the complex, so there may be 6 Base-X tents (1905sq-ft just in tents, 137sq-ft for the S-250+roof tent, 720sq-ft for the first floor of the bus) total in my complex when I'm done I guess? 2,762sq-ft of enclosed sheltered space - plus three 20x10 pop-up canopies add another 600 square feet of covered area.