The biggest issue you're going to find is that the Tampa Convention Center is not only water front property, but there isn't a whole lot of options within walking distance of the convention center. There is one bar & grill that is right outside the convention center, but you can sit an entire hour without even having someone show up to your table and everything else is driving distance. There IS a Starbucks in the lobby of the Embassy (connects to the convention center) but I can't think of anything else that is close or easy to get to. Parking each day at the convention center is going to run you around $10 (in the parking garage) so take that into account. You're also going to need to activate the SunPass that the rental car has installed (we just did a month with Budget and each car had one, so I'm assuming this is standard) because Tampa doesn't have any cash tolls and unless you know your way around or you set your GPS up specifically to avoid toll roads (not even sure this is possible to get the CC tbh) it's SunPass or Pay-Per-License-Plate so you're getting charged either way.
Tampa is an amazing city, one we almost decided to move to, but why on Earth they put the D2 Summit there is a mystery to me. It's not build for this type of competition, imo (and something I said when it first got brought up) and will likely cost as much as the Summit in Disney. They should have done it a weekend apart. Disney and Orlando are expensive places to compete at, but at least they're prepared for the transportation and lodging issues, Tampa? Not so much.