Volcan ........... David areas.

I just soent 3 months in Volcán. There are about 5 mercados in this tiny town. Not a whole lot to do there though. Not an abundance of rentals in my opinion.
You are a 90 bus ride from David. The temperature of Volcán is perfect. Rainy season it will rain every afternoon. Dry season is often horribly windy.
I walked everywhere in Volcán. It is very nice, but in the long term, little to do there.

Volcan has grown a lot in the last 4 years. We disagree with what Janet said. If you are an outdoor/nature  person there is a ton of things to do! If you are into night life that is not the place for you.
David has everything you would want, airport,shopping, hospitals, close to beaches and Costa Rica border, although for us, a tad too hot.

For affordability, these are two great areas.
Good luck!

Thanks Janet119 and sailcompania for your replies.  Are there any ways I can access online avenues of classifieds etc... That would have listings of Casitas and Apartments that are for rent, (on the low side), not a rich guy.

Try this:

Encuentra24.com: Classifieds


and you  can google  and find a ton more