@rugbygirl - What it means to be objective is always an open question, and you're right, it's impossible - for more reasons than language alone. Human beings are subjective by their very nature. We see the world through our own filters and it is unreasonable to expect otherwise. Usually, the best we can do is try to be aware of those filters and account for them.
Adjectives are always loaded. If you are really trying to describe objectively, it can help to avoid them altogether. If you want to say that someone was thrifty/stingy, instead say something like, "Although the family income was well above average, she continued to line dry the family clothing" or "His wife, homemaker, often complained to friends that he did not give her enough money to buy groceries." If true, those are revealing statements; no need for *you* to tell the reader what they mean.