Hapkido was founded by Choi Yong Sool (1904-1986), who, from 1919 to the beginning of WWII, had studied Daito-ryu Aiki JuJitsu in Japan.

It is said that Choi learned this art from its headmaster Takeda Sokaku. Daito-ryu Aiki JuJitsu is one of the arts Morihei Ueshiba synthesized into Aikido. Around 1939-40 Choi returned to his native Korea and combined his kowledge of Aiki Jujitsu with the Korean system of Hwarang-Do and at a latter date Taekyon.

From what has been stated to me is that Choi never mastered the vast Aiki JuJitsu system of Daito-ryu and only got to about the first circle of mastery in the system as there are three levels of techniques.

Daito-ryu Aiki JuJitsu comes from the Tekada family and is also responsible for many of the techniques you seen in Aikido.

As to where the gathered the tools to create there family system of Daito-ryu I have no clue.

Regards