Hmmm... I see what you did here 
Doing the same thing you want to do here, I can tell you there is definitely a market for cheap landing pages.
You'll end up having to give support for the silliest little questions.
"I bought a landing page... now what? Do I have to get hosting or can I just put it on freewebs (or wherever)?"
"How do I change that button in to a link?"
etc, etc.
Pricing: I sold 5 times as many $5 LPs as I did $15 LPs. Split test the prices a bit and found that would probably be the most profitable.

Doing the same thing you want to do here, I can tell you there is definitely a market for cheap landing pages.
You'll end up having to give support for the silliest little questions.
"I bought a landing page... now what? Do I have to get hosting or can I just put it on freewebs (or wherever)?"
"How do I change that button in to a link?"
etc, etc.
Pricing: I sold 5 times as many $5 LPs as I did $15 LPs. Split test the prices a bit and found that would probably be the most profitable.