Having many years experience as both a webmaster and a designer, my best advice to you is not to under-value your work. It hurts you, and the industry.
If your templates are superior quality (with 15 years experience they should be pretty darn sweet, especially considering that TGP and freesite business models have only been around for about 12 ....), you should have no problems procuring business at going rates - which are currently about $20-25 for a good TGP template, and maybe $45-50 for a good freesite.
When I started doing TGP templates, I was getting $50 each with no discounts on bulk orders, because I was too busy! Then as offshore outsource companies began to flood the market with prices that were half of what I was charging, they lowered the bar, and that quickly became the new industry going rate ..
When you sell a product much cheaper than it's going value, you not only cheat yourself, but you make people question what is the matter with your product also?
If you have a decent product, do not be ashamed to ask its going rate -
HAVE PRIDE IN YOUR WORK!
Good Luck!
FF