All over Zanzibar, particularly in Stone Town and on the beaches, you will be approached by what are referred to as papasi. These are individuals that are trying to sell you tours and activities, which are often at the fraction of a price of what you pay in the hotel. When choosing tours or tour operators, please bear in mind the following:

 - beach boys sell tours to tourists on the beach. Sometimes they overcharge you, or they are selling it at low cost. When considering to book a tour this way, shop around a bit first in order to get a good price - you don't want to be ripped off, but you also want to make sure that the guide earns some money himself. 

- be careful of papasi in Stone Town - some are drug addicts and just want to make some fast money.

- never hand money over BEFORE the trip - not even a deposit. It might be that they ask you for some money at the beginning of the trip, but usually it is ok to pay at the end of the service. 

- so far, you tend to get the whole price and no funny surprises in Zanzibar (like, for example, that at the end of the tour they suddenly tell you that this and this was not included in the price). Just make sure at the beginning of what is included

- using beach boys means that you support locals, but you never know which ones are honest and which ones are trying to screw you over. 

- sometimes it might be better to go via a licensed tour operator. The problem is that these tend to be more expensive - however, that is not their fault, the overheads because of taxes and government charges can be extortionate, and it's not their fault that they have to charge higher prices (in return for proper licensing and sticking to the rules, instead of the 'black market' of papasi or beach boys.

It is worth checking on the Internet for some tour operators beforehand. The big ones tend to be linked to the government and work straight into the government pockets. Do a little search and digging and you'll find smaller tour operators that are truly local and will give you a very personalised experience, because they genuinely care about showing guests their island while trying to make a better living.