One way to narrow down your options is to consider what type of fitness writing you're most interested in. For example, do you want to write workout routines, share your own personal fitness journey or keep your readers informed.
Taking trips during holidays and peak seasons can affect the cost of your trip. From the price of airlines to accommodations and food, the prices for these things can hike up. Do your research on your destination to figure out what is the best time to travel there and to either just before or right after that time. Airlines and hotels will lower their prices in the off-season as a way to attract customers.