I picked up this one from HomeDepot last week and it worked perfectly for seating my troublesome tubeless tires/wheels. It is 6 gallon. I imagine that a 3 would be fine, but check what the ‘max pressure’ is. If you want to seat tubeless you need a good initial strong burst of pressure.
And yes you will need to buy a hose / attachments / presta chuck separately. The compressor doesn’t come with anything.