This is a good question. Things I've spent most money on have been functional nutrition and acupuncture.
With acupuncture I'd feel benefit for a few days then effect wears off, a bit like medication that manages but doesn't cure. After at least a year I called it quits because felt it didn't get to root of problem. On the other hand, I started it at a point I felt I'd have to give up work but maintained working part time all the way through having acupuncture plus about a year after. Then had relapse and now can't get to acupuncture appointments! Probably completely unrelated but who knows?
I was surprised with nutrition how much better I can feel with tweaks but some costs maybe unnecessary. If you have cognitive ability, try the Mendus Diet study for free (recording diet and symptoms in detail for a few weeks then analysed stats and get personal results).
www.mendus.org/diet-study-home.html
Experimenting with salt made big improvement for me to but turns out I have POTS too.
Liquid valerian eg Salus helped sleep and in turn everything else
I've started a thread about interpreting 23andme data if you go down that route too
http://forums.phoenixrising.me/index.php?posts/717683/
On my blog I try to recommend cheap and free ideas that may help (no illusion these are cures!): tipsforme.wordpress.com select category Resource
In all honesty alternative treatments help somewhat but pale into insignificance compared to appropriate medication eg for me bisoprolol and ivabradine.