Our volunteer transportation problem

Here the problem. Parents I need your input so please please please comment or text me.  

Mérida is a rich city, and we live and study in a wealthy area.  In order to volunteer with those who need services we have to travel to where they live which is FAR.   We have to take 2 buses to get there.  The bus system here is not like the US... There is no set schedule, if the bus is full or if the driver is ready for his break they will pass you by.  

My main concern is us getting stranded out at the volunteer site if buses decide not to come.  Also the several buses that it takes for us to travel in such a large group.  

Ok now that you understand part of the problem here are our proposed solutions.

1. Private transportation for $1000 PESOS a day which comes to 60.24USD a day. Divided by 21 of us $2.87USD xs 8 days equals $22.94 per person.  

The students ALL say that they don't have enough money to pay for it.  This comes up to be $14 more expensive than their current travel costs.  The boys are eating their body weight in snacks and have been spending a ton on food. The kids want to continue to travel the way we did, they say they feel safe etc but I don't like this at all for safety and control reasons. 

To us adults the extra costs is worth the safety and reliability that the private transportation offers.  

There may be the possibility of paying the host moms to drive their groups to and from but they haven't gotten back to us on that. 

So with all that being said parents, what are your thoughts suggestions and questions? Also for those who propose that we continue with the private transportation will you be able to send that extra $23 via western union to cover the costs?