You need to allow at least for armour to be moved to the stash, otherwise you can never buy a better armour for a fighter, since they can't have several armours at once. And once you have made this necessary exception for armour, the 'put away the clipper' rule is even harder to justify for the rest.
The end-of-turf-war shenanigans discussed above are the result of the gang rating trying to do two different things at once and failing at both. There should be two separate values: a gang rating (cumulated value of everything the gang owns, including credits, items in the stash and special territories) and a crew rating (cumulated value of all fighters used for the current game). The 2000/3000 credits limit at the end of a Turf War should apply to the former, and the latter would be used to award underdog bonus (extra XP, extra credits, extra tactic cards, etc.)