Being specific helps. Life changed a lot during that period, it's hard to generalize. Also, not everybody lived in the same conditions. However, I guess you want to compare our current concert experience with that of the ole days, and I'll give it a go.

How rich would I have to be to go to a concert?

First, what do you mean by concert? If you have this in mind, sorry but it was not quite like that. You can have big events, but without amplified sound you won't get to THAT scale. If you are thinking about a "classical music" concert, that didn't exist, either...

Concerts as we know them developed out of informal occasions where music was performed with other kinds of activities. We are used to music by the sake of music, it was not really quite like that. Music was NOT the centre of attention! Such an event was born between the 17th and 18th century. Of course, "serious listening" existed. It happened in the courts and in churches, but in general the context would be different.

What else would be different? Well, there weren't big orchestras in the 16th-17th centuries. We start to see bigger ensembles in the 18th, but the big orchestras in big halls are more of a 19th century thing. The same would happen for ballet, it was not the same kind of event we have now (but I'll leave that for the dance experts). What we call opera today started in the last years of the 16th century, and it was performed with much smaller orchestras and fewer people on stage.

Opera was performed at first in the palaces of the super rich in Italy. So you would not get there unless you were highborn, super rich, or performing the damn thing.

Louis XIV of France wanted a very active artistic life in his court. He hired lots of musicians, dancers and what not. He would have musicians for outdoors events, religious ceremonies, or some more social/stately functions. I don't exactly know who would be invited to each of those events, but it was not your average person.

The collapse of court and church music (because of war and social turmoil) gave origin to public concerts, this started to happen around the 17th century. In the 18th century, we see musicians going from being court/church servants to independent professionals and even entrepreneurs. We see public halls being opened, and people being able to buy tickets to go to some concert. And then we have the problem of who could afford doing such a thing.

The "democratization" of concert music started in the 19th century, and the process continued during the 20th century. See, some people still complain about young guys attending to a concert wearing jeans and a tshirt (we just managed to get there on time after finishing school, or work, or whatever!).

Assuming I liked the music and wanted to hear it again

Wait, what? You want to listen to the same thing AGAIN?! Today we are used to listen to the same music ad nauseam. Recording technologies allow for that, and also we developed this obsession with keeping music "alive" during the 19th century.

Yes, it was attempted to freeze some church music in time, to be able to have it performed "in the proper way," but that doesn't mean you would listen to exactly the same music at every service. People were not really into playing old music. Most works were performed few times, and then people moved on. Musicians were also expected to improvise to some degree...

do I have an alternative other than again paying for the concert?

As I said, there was no such thing for a while. And once there was, you would not pay for it (unless you were the one organizing the event). It is until later that you could actually buy tickets for an event of this kind.

Once there were concerts, and you were able to buy a ticket, you would probably have very few chances to listen to what you liked. It was normal for people to ask musicians to repeat something. See, people were interacting with opera singers, they would ask for arias to be sung again. If it was a particularly great aria and/or a superb performance, people would actually start to pay attention (these events were kind of... different, when you compare them to the modern "classical" concert) and they would ask (perhaps even demand) the music to be repeated. People would ask Beethoven (or some other musician) to perform some movement of the sonata/symphony again. Beethoven some times complained about people asking for some silly part, instead of the ones he considered to be worthy of repeating.

Also, you would either pay people to play the music for you, go to a place with musicians, or play the music yourself. It was a world in which there only were live performances. Think about that, there was no music unless somebody was playing it. How many people capable of making music does the average person know today?

Your question is interesting, and it leads to many, many interesting and weird historical things. But it's too vague to be properly answered.

Could you narrow this down to a region and century?