If its a club membership as opposed to deeded property and outside of your country of residence, then defaulting can be a relatively straightforward option, you will likely loose any money you already paid and get threatening letters, but there may be little more than tht, that actually happens.
Take a bit of time to look into things and assess your personal situation as to the probable and potential impacts and then make a decision from there. It really is a personal decision.
Do not, however engage the services of any exit company, they will simply take more of your money and do what you can do anyway.