Make sure you clarify what's included on the bus (music, lights, drinks, etc.) right away.

Discuss the time and number of stops with the company.

Let your friends know in advance if you need to chip in—this is standard practice, but it's important to mention it upfront, not at the last minute.

Also, don't just choose the cheapest option, choose a reputable company. Sometimes, under the guise of a party bus, they offer regular transportation with no atmosphere (people complain about this), so it's better to pay a little extra to get a real party experience, not just a shuttle.

One thing I can really recommend is party bus hire in London . They have buses for that number of guests. Inside, they have decent sound, lighting and soft seats. It's essentially a mini club on wheels. You can plan a route, pick everyone up, stop at a couple of bars and not worry about logistics. The driver knows the city so you don't have to worry about how everyone will get around.