Assassins was — and I guess still is — a Stephen Sondheim musical that a lot of Sondheim fans seem to forget about. They also forget that it was written by John Weidman, whose name rarely makes it onto the posters and ads when the show is now produced.
And it's produced a lot because it's good for small theaters or theatrical companies that have a lot of young actors who want to get on the stage. I've seen three mountings of the show in my lifetime and none of them had elaborate costuming or sets or more than a few musicians. It's not Sondheim's best show but it might be the cheapest to produce.
If you ever decide to do this, this video might be of value to you. It's Sondheim and Weidman basically telling you what to keep in mind…