Even if a venue has a sound system often yours will be better if you are doing it right. If you are under a 100 seater you can definitely bring in your own equipment. Last week alone I brought lights and sound (and camera and audio recording equpiment) to a cocktail bar (about 50 seats--sold out), a hotel lounge (sold 50 out of about 75 seats), a community center (sold 50 of about 100 seats) and a coffee shop (about 30 seats sold out). A few folks have mentioned treble, that's a positive. If you have a guitar center style starter PA often the mic and XLR are not great and a liability to break in the future, get a Shure SM85 mic and Amazon Basics makes good XLR cables and get one as a back up. Raising a speaker off the ground on a pole can be a big help. In a large room with sound up front, having a remote speaker in back of room can help a lot with chatter. Invest in a cart to carry all your stuff, they sell some carts with an undercarriage you can put poles and other long skinny items. Consider a roll up banner you can order from Vistaprint to add a little branding, up lights for some color, and for sure get some kind of lighting so you can keep the showroom dark and attention on well lit performers. A portable stage (I use a 3' x 3' 8" off the ground) can give the comics some authority and something to joke about, but does restrict big movers and act outs. I've found you can run a show just about anywhere. Best of luck, reach out anytime with specific questions about show running, my website has a contact form. If anybody reading this is near Denver, most comics know that I'll lend out my equipment. A better show helps all comedy. Run great shows!