Finished our first joint build together and it turned out better than I expected

My wife and I did basially the same thing last winter with a Blacktron theme instead. She had a bin of her dad's old parts and I brought the newer trans-yellow from my own stock, and the mismatch drove me nuts til we agreed to sort everything by color before building anything. That one step saved the whole project, honestly. We split it the same way too, I did the vehicles and she did the base plates and the little details like computer panels and antenna rigs. The moon base idea is worth taking seriously. We went from a single display to a two-foot by three-foot layout on a plywood board, and the nice part is you can build it in sections so it still comes apart for moving. Ours sits on an IKEA Lack shelf and the weight is fine, but keep the base board light if you ever plan to wall mount it.

One thing I wish we had done earlier is agree on a parts budget before the second weekend. I kept ordering BrickLink lots to finish her section and she had no idea the build cost me forty bucks in minifigure accessories alone. She still teases me about it. Enjoy the slippery slope, the next thing you know you are arguing about wether the moon base needs a monorail.

Funny reading this because my partner and I tried the whole shared-build thing and it nearly ended us, so now we build side by side instead. Two separate models on the same shelf, same theme, zero arguments. She does her Classic Space outpost, I do my Monorail setup, and they're close enough that they read as one display from across the room. The dining table looks like a LEGO store on a Sunday and we both just get to zone out with our own piles. The one rule we landed on is no parts poaching. I bought a big tub of trans-red plates specifically for her because she kept stealing mine, and honestly that fixed more friction than any sorting system ever did. We also do a grocery-store-style swap where she takes my extra minifig accessories and I take her baseplates she'd never use.

On the moon base plan, word of warning from someone who got talked into a nine-square-foot city layout: agree on the footprint before you buy a single plate. Ours outgrew the shelf in about two months and now half of it lives on a folding table I have to move every time we have people over. Worth it, but I'd budget the surface space first if she's anything like my wife.

Regarding the claw versus magnet arguement, I would quietly keep one magnet bar in the parts pile anyway, because a M:Tron build with no working magnet always feels slightly wrong to me, like a fire station with no pole. My compromise on a similar build was a claw on one arm and a small magnet module on the base as a cargo loader detail, which honestly satisfied both parties and took about six pieces. Also, once the moon base talk turns serious, photograph the display from four angles before you ever take it apart, because I lost the design of a custom layout for two years and reconstructing it from memory was worse than any color clash.

Update — I went with the hybrid approach from one of the replies. We decided to keep a magnet bar hidden in the part pile anyway. It solved the whole argument because while the claws look better, having a functional magnet makes the thing feel complete. It really tied the design together.