Sorry for a delay, I randomly came across this post and wanted to give you my 'two cents' on this matter.
I am a bus pastor who recently had to convience a senior pastor of a very similar circumstance. When I first got here, we had two buses, an 89 that held 22 and a 91 that claims to hold 48, but I think more like 30.
Before I took the bus pastor title, the church had spent over $6K on credit to rebuild the 91 engine. As a former mechanic, I think that is crazy! but it was before I got here so I could do nothing about it, just pay the bill. About a week after getting the 91 back on the road, another pastor blew the transmission on the 89. Sold it for parts. Now we are left with a 91 that breaks down very often.
The church had raised some funds to buy another bus, but what we really needed was two buses. And Praise the Lord, we will be picking up two buses on Monday.
Here is my suggestion along with my Biblical reasons (I am a BAPTIST, I want a