While there are no hard and fast rules as to what you will see in a set of HOA rules the following are the areas you will see covered.
The exterior of your unit will be governed in all areas from what you can have on your patio to your front door color. Some, because of insurance reasons will restrict the use of barbeques and other outdoor activities. Parking restrictions are always included.
There will be a section in the rules governing the payment or lack of payment of your HOA fee.
There will be noise and occupancy rules to follow.
In the end, I always recommend to anyone buying into a planned unit development governed by an HOA become part of the board and serve. That is the only to effect change or reign in spending when it is needed.
If you have a specific question I am happy to answer it.