Gittin 51: Partial Debts, Lost Items

I am forced to admit that I am in way over my head.  Gittin has become a conversation about property rights and my lack of background leaves me frustrated with my less than partial understandings.  Having read other online resources, I am still reeling.  

Some very basic ideas:

• no interest is paid on loans
• a person might pay back part of a loan at one time and the remainder later
• inheritance has specific rules, including the provision of dowries at one tenth of the inheritance 
• a husband provides for his wife's daughter as a stipulation of their ketuba
• when a person finds part of a lost item, no oath is required to prove address the remainder of the lost time
• those who are called minors, deaf-mutes or imbeciles are not permitted to make claims like others and thus oaths are not required in response to those claims
• the rabbis choose to believe that people will not lie to each others' faces about what they have found or what they owe