It's pretty easy to repair common parts at low-level repair stations now (they were completely overhauled in Alpha
, nothing like it used to be that would've been mentioned in this thread. Still, it's not a panacea--you'll have to selectively repair only parts that are really important to you due to the limit on how much you can get out of it (especially without hackware).
And while you are unlikely to find storage units lying around in higher floors, it's very easy to find Haulers, and you can just take the largest storage unit in the game directly from them! Or before you find them, take medium-sized storage from Recyclers, which are everywhere, or small storage from the Workers. The idea of harvesting parts from hostiles known to carry them can be crucial for survival in tighter spots.
Also, it's not just -10. Currently the lowest three floors of the game each have a guaranteed dedicated area with tons of storage parts to choose from (the "storage cache"). It's only when you reach the mid/late-game where you'll be more likely to rely on stealing or building them.
Also, as a combat bot I always carry spare storage in my inventory itself.