Hazrat Aamir bin Fuhayrah (radhiyallahu ‘anhu) (the freed slave of Hazrat Abu Bakr (radhiyallahu ‘anhu)) would come to the cave after esha when the darkness had set in. He would bring a few she goats with him so that Rasulullah (sallallahu ‘alaihi wasallam) and Hazrat Abu Bakr (radhiyallahu ‘anhu) could drink whatever milk they required. This is how they passed three nights in the cave.
On the fourth morning, Abdullah bin Uraiqit (who was hired and appointed as their guide to Madinah Munawwarah), as per his promise, came to the cave with two she-camels. He left the normal route which people would use when traveling to Madinah Munawwarah, and instead took them on the more unfamiliar coastal route to Madinah Munawwarah.
Rasulullah (sallallahu ‘alaihi wasallam) rode on one camel while Hazrat Abu Bakr (radhiyallahu ‘anhu) rode on the other camel. Hazrat Abu Bakr (radhiyallahu ‘anhu) also brought his emancipated slave, Hazrat Aamir bin Fuhayrah (radhiyallahu ‘anhu), with him to serve them, and he seated him behind him on the same camel. Abdullah bin Uraiqit mounted his own camel, and since he was the guide, he would ride ahead of them to show them the way.
At the time when Hazrat Abu Bakr (radhiyallahu ‘anhu) embraced Islam, he had forty thousand dirhams in his possession. He had spent most of this amount in the path of Allah and in purchasing slaves to set them free for the pleasure of Allah Ta‘ala. Thus, at the time of performing hijrah, he only had five thousand dirhams left from the original amount of forty thousand. When departing for the hijrah, Hazrat Abu Bakr (radhiyallahu ‘anhu) took this money along as well, and on coming to Madinah Munawwarah, he spent even this amount entirely in purchasing the land for Musjid-e-Nabawi and in other deeni projects. Hazrat Aa’ishah (radhiyallahu ‘anha) says, “At the time when Hazrat Abu Bakr (radhiyallahu ‘anhu) passed away, he did not leave behind a single dinar nor dirham.”
Nevertheless, Abdullah bin Uraiqit travelled with Rasulullah (sallallahu ‘alaihi wasallam) and Hazrat Abu Bakr (radhiyallahu ‘anhu), and they departed from the lower regions of Makkah Mukarramah, heading towards the coast. From here, they continued traveling, passing by the lower regions of Usfaan, travelling one manzil at a time (i.e. a certain distance), until they ultimately entered Quba (a locality on the outskirts of Madinah Munawwarah).
(Extracted from Seeratul Mustafa 1/384-385)