DO NOT DO INNER THIGHS!!!!!!
I had lipo a year ago and I am also athletic 5'4" 120lbs and you are correct you can work your butt off and never get the thigh area contoured like we want. I did my inner thighs even after reading the "horror" stories thinking oh that won't happen to me - WRONG!! I didn't do the outer b/c I didn't need that area. Anyway, the lipo did solve one problem and that was the rubbing/friction however it is so obvious that I had something done. The inner thigh area looks bumpy/wavy and the skin just didn't tighten back up like I thought it would. Granted I'm 42 but still I thought it would look better than it does. I'm now doing endermologie/tri active and luckily that has helped smooth the areas out some but they will never look the same.
I also did the flank area and this was the second time I have had that area done and still no results. And just so you know that area hurts like you know what for some reason.
Would I do it all again, probably. As I said the friction issue was more my problem and walking the beaches on vacations was just impossible for me as I would break out in rashes. Not a pretty picture

but now I have a different issue with that area.
I would try tri active first atleast in the inner thigh area first before lipo.
I hope this helps and I don't mean to be so blunt but I promise you I should have paid more attention to all the others who had bad results. Oh well live and learn. Good luck and let me know what you decide.