Another tip for budget travelers - i don't know if it is still running but the margaritaville shuttle bus is free. It used to run down from the west end about ten in the morning and returns at 4 in the afternoon. The drivers don't know, or care if you eat and or drink at margaritaville. I would tip the drivers and then they will be happy to pick you up. I was on a tight budget so I would tip when the bus was empty but not so much when it was full. I'ts a good back up when you are in the right place at the right time.
Be sure you bring some really good walking shoes. The more you walk, the less you spend. Also bring a day pack so you can carry any food and drink that you want to by in town before you head home. An insulated bag of some sort is also really handy and guarantees a cool drink when you get home.
I hear there is a free "one love pub crawl shuttle bus" as well
I don't want to hear any more worrying Medi! Once you go you will know! If you need to move I am sure you will have no problem moving. There is a good chance you will be very happy at Somerset. Nothing you are thinking about right now will be what actually goes down when you get there. You are going on an adventure. The worst thing that can happen is you have to spend more then you planned and cut your trip short. Heck, three good weeks is better then four so- so weeks.