For no more than you plan to use it, I would get a Sonos Beam and a pair of Sonos Ones for surround rears. When playing Audio, you can use the Play Ones in stereo or the whole system. You can also take the Ones anywhere you want to listen to stereo, like the patio, etc.You might even start with the Beam as it may be sufficient.
If separate TV audio is not required, you could get one or two Sonos Fives. I use one in the garage and it also plays plenty loud enough for washing the car outside the garage. The app streams from all the major services and from my PC server which contains my ripped music collection. Just get white so it doesn’t show every speck of dust.