There are buses nearby, but the hills may be prohibitively steep. There is some street parking, a small lot across the street between Madison and Pike, and some downstairs garage parking across the street on 14th (intended for shops on that block, not intended for the venue).
Staff persons at this venue are usually nice and helpful, it's possible/potentially likely they would allow disabled patrons in first
There is a small ramp and lip to enter the venue door, then there is a wide ramp up to enter into the venue which leads to the "box office" for tickets, then there is a ramp down into the main space in front of the stage. There is also a raised viewing area behind the bar toward the entrance, but there is a step up to it and no ramp.
There is a padded bench built into the wall at the far left side of the stage which wraps around to the back of the main floor area. There is also some seating and tables in the bar and in the raised viewing area behind the bar. However it may be difficult to see over the crowd at a well-attended show.
The door for the accessible stall opens into the stall which makes maneuverability in the stall difficult.
The venue's website says to email them in advance to reserve space if needed.