I have read about attenuators but I didn’t realise there was one so small and affordable. Any drawbacks to this?I don't know how a 50-watt running at 5-watt would compare, but my old Blackstar was a 5-watter and that had plenty of volume. Could easily be used at home-friendly volumes but loud enough to get a nice tone. I even used it playing with bands and it still managed to cut through, though I'd recommend a higher-wattage amp for that purpose.
If it still is too loud, an attenuator is the solution. The JHS Pedals Little Black Box looks pretty good, is reasonably priced and is only the size of a mini effects pedal.