I was wondering how much a used Mesa bass 400 not the 400+ should sell for. Also is it real expensive to retube these things? Is it expensive to have work done on them? The power switch on this one doesn't work, It's always on. You can use the standby to cut sound but it is still drawing current. I'd say on a scale of 1-10 condition wise it's like a 6 or a 7. Thanks alot for any help you have for me.