I think this is a good idea, but politicians will find a way to use this concept for corruption, and I envision how will they do it...
Politician 1 will claim an essential need for their family (Obviously not needed) but claimed to be essential, and politicians 2 3 4 and 5 will be his backer that it is essential thus will be approved. And this will go on and on, and by the end they will have high end gadgets, house and lots for their children's, multiple luxary cars, etc.
Well, this won't work. Maybe they will gain some wealth, but they cannot keep it after next elections. Politicians simply cannot buy anything - because they do not have any money. Politicians will be a special kind of servants - they get humble living, some clothes, food to survive...
Ohhh, so all of their assets that they deemed "necessary' will be confiscated after their term? is that how will this work?, so even if the family is living a luxary life while the politician is in position, they will go back after the term ends. Oh nice
But doesn't that will affect their children mentally, and emotionally as their items will be gone without their knowing, thus having issues.