This is going to be fun

howdy y'all! I just thought I would introduce myself. I am down here in Alabama (and would love a training buddy so if any of you are close...). I am a veteran martial artist who had to quit training due to health 'issues.' After slumping around in grief for a while, I have decided that this is the next incarnation of little ole rockheaded me. I can't wait! Before my martial arts days, I had done a fair amount of running on what are now some seriously tempermental hips. Running and anything too stressful on the joints is now out of the question (no matter how defiant I am). That will make triathlon training a little lopsided, but who cares, I'll just have to be that much better at the other two! I can do my silly little hypermobile walk for the run part. The catch is that I have not done much biking or swimming either. I can get from point A to B, but not necessarily in a stylish manner. Currently I have a mountain bike with street tires. I know I will need to buy another. Does anyone have any advice about buying a more economical road bike first or should I try to scrape the funds for a tri bike? Thanks! By the way, this is an incredible site!