"They certainly would have not have started out on the instruments they had in the early days especially in 50/60's working class Liverpool unless they had a bob or two."

My understanding is - and I'll have to do some research to confirm this - is that the types of instruments they played at first were rather inexpensive at the time. Rickenbackers, Hofners and Epiphones were not the Fenders and Gibsons they played later. The reason those instruments became sought after later on is because the Hofners and Ricks were identified with the Beatles.