Weight-loss, weight gain, and Fursuits?

I am 50 pounds overweight, and I plan on losing it over the next year. If I make a bodysuit and lose weight, is there any way I can make it fit again? Or should I wait until I reach my goal weight before making the body part of the suit? Also, If I GAIN weight after I make it (I don't plan to, but it may happen, lol), is it possible to "let it out"? If I pour out my money and time on a fursuit that I am proud of, I don't want it to not fit! Has anyone ever ran into an issue like this? What would be my best plan of action?

Sorry if this is poorly worded---I am extremely sick ATM. @.@