Noticed another thing:
The timer clocks for generating gold and gems from properties re-start after you collect. You cnnot let them keep generating. A property does not start making more gold or gems for you until you collect the last batch.
And remember to gift the best items you can. You are joining their crew so gift the items you would want.. so the best cannon, weapons, amulets, and tackle you can.. even if you have to exit and re-enter the gift screen 10 times to get a good item to show.