Where should I practice my euphonium?

OK, I don’t have a euphonium (though I’m considering renting one, really!). But I live in a small apartment and don’t want my amateur noisemaking to bother my neighbors…or my wife. I’m not an aspiring professional musician, just an amateur who wants to have a little euphoni-fun. Any solution would need to be cheap and convenient.

So where should I go? Do schools let you rent practice rooms? Are there studio spaces or something where people pursuing creative arts – and honestly, what’s more creative than euphonium-playing? – can timeshare?

In short, if you’ve had a similar problem, how did you solve it?

I’ve got a buddy that runs a music store. He does have practice rooms available in his building, and usually rents them to music teachers to use while giving lessons. I suspect he’d also be willing to rent one to someone wanting to practice an instrument, probably at an hourly rate. So maybe other music stores near you do something similar?

Most colleges have music rooms for student use. If they aren’t being used otherwise, no one cares if you’re not a student.

Supposedly, George Harrison used one to write “Here Comes the Sun” and “Blue Jay Way” while in his garden.

You can buy practice mutes for home use. Here’s one, for example.
http://www.warwickmusic.com/mutes/euphonium/wick+euphonium+practice+mute
This is on the pricey side. They can be had for much less.