What is a fair profit sharing plan for a small business??

this year i have been helping my brother in the background
and my parents have been helping him by running the office
and bookkeeping for no charge.

The things that I will be doing--and have been doing- is
to gather all customer and job data that filled 3 large
boxes and transferred all the bits and pieces to a viable
franklin covery electronic system so anything on a particular
customer or class of customers can be accessed instantly.

this has taken me about 3 months at 3-4 hours per day to
accompllsh. in addition to that there are about 20 areas
of the business that are in need of attention and i have
done due diligence and listed the progress to date and
the exact steps needed to accomplish those objectives.

the season is about ready to start and once it does each
day means a pile of papers including receipts, time cards,
estimates, and job reports that need to be entered and manipulated to produce the next days to do list--what is
a fair payment for this???

one way would be to pick an hourly rate (aka - what would it take him to hire someone) and apply that to the estimated number of hours you've worked. let's assume 20 days per month for 3 months. That's 60 days. at 3 hours a day that's 180 hours. Assuming a 15-20/hr that would translate to $2700-$3600 total.