It helps in the sense that there are going to be very clear rules and precedents from the hadith, the Islamic collection of interpretations of the Khoran which expands on the Shariah, the basic tenets of Islamic laws that set out how one should live their life. (For instance, the Quran/Shariah doesn't specifically address lawsuits or whether one can beat their wife, but the Hadith does.)
The problem is threefold - first, the Hadith is as vast, arcane and byzantine as any medieval legal system, maybe more so because it's a religious legal system, and one that often relies on interpretation to fit the specifics of a case. Second, there are in fact two collections of hadiths - one for Shi`ism and one for Sunnism (Shi'ite and Sunni - loosely speaking the orthodox and the mystic sides of Islam, respectively - and a city would be ruled by one or the other, as determined by the government at the time). Third, over time different emphasis was put on different parts of the Haddith, in much the same way that Catholicism has interpreted/approached certain "sins" in different parts of their history. (See "butter tower".)
The question of a dispute would go to one or more of the local imams, the "learned scholars/leaders of Islam" (my very loose translation*), who would harrumph and opine and consult and deliver an interpretation based on Islamic law (as based on their sect's collection of the hadiths).
- Islam does not have a formal hierarchy of clerics - there is no single Pope, and no Cardinals and Archbishops and bishops and priests. There is, in order, The Khoran, which is the word of the Prophet Mohammed. Then there are ayatollahs, who are recognized and respected as most learned and wise in the ways of Islam.* Then there are imams, who are similar but not as widely recognized, but who are still learned. And then there are the devout, who are guided by the first verse of the Khoran:
(O Beloved!) Read (commencing) with the Name of Allah, Who has created (everything)... Read and your Lord is Most Generous, Who taught man (reading and writing) by the pen, Who (besides that) taught man (all that) which he did not know.
So every good (literate) Muslim is going to study the Khoran, and those who are not literate will try to become so, and those who are not will meanwhile listen to those who are, and those who do so long enough may become imams (and possibly ayatollahs), just by nature of succeeding in this holy effort. What this creates is a long continuum of "learned-ness", with ayatollahs at the top - and imams (individually or - more likely - as a group) fill the role of the people's religious teachers, speaking in mosques (usually informally), teaching and addressing questions, and resolving community issues like the one you mention, based on their recognized knowledge and understanding of the existing religious doctrine.
(* There is no one who "officially appoints" or authorizes the status of Ayatollah, so some are acclaimed by common agreement of the populace, others are more "self-appointed", if with a proportionally smaller following and recognition.)
So, when I say "oy", what I mean is that without finding an Islamic scholar, without someone who has studied the hadiths and practically become an imam one's self, you're not going to find a concrete answer.
As-salamu alaykum - peace be upon you.