Bank statements. One sort of financial record is a bank statement. Your bank will regularly send a statement containing information showing income (credits) and outgoings (debits) on your bank account.
They're synonyms. Gain is the most general. Attain usually means to reach a goal or milestone (he attained the rank of captain). Obtain usually implies careful planning or some effort to get to the thing or goal. But they have probably something like 80% overlap in meaning.
English Collins Dictionary-English synonyms & Thesaurus &nbsp. attain (attains 3rd person present) (attaining present participle) (attained past tense & past participle) 1 verb If you attain something, you gain it or achieve it, often after a lot of effort.