I am not sure of the wisdom of early declarations by Labour Leadership wannabes before the timetable or rules for the contest have been agreed by Labour's ruling National Executive Committee (NEC). The last Leader/Deputy elections were mired with issues about campaign donations as candidates amassed five and six-figure sums to woo Labour Party members.
According to report at the time the Deputy Leadership candidates war chests were as little as £4,000 declared by Hilary Benn to an eye-watering £180,000-£200,000 by Peter Hain. A similarly large sum was raised by the only valid candidate for the Leadership - Gordon Brown.
In the wake of the anonymous donations scandal to the Labour Party itself which swept away General Secretary Peter Watt in controversial crcumstances, now interim Labour Party Leader Harriet Harman was forced to pay back £5,000 given to her by a property developer who has secretly bankrolled Labour to the tune of £600,000. Peter Hain was obliged to resign as Secretary of State for Work and Pensions to defend himself in the face of a police inquiry into his campaign donations triggered by the Electoral Commission. And he did so successfully, but it took a long time.So the best advice to all concerned would be proceed with caution, and making sure you keep very good records of both donations and expenses.