Hey man. Take'er easy.

I know you prob don't wanna spend the cash, but sometimes you gotta.

I use an 12x12 by 12 tall exo terra. I put cardboard over the entire top portions (two screen parts). I left an opening for a 50 watt black light in a mini deep dome fixture. I use a digital hydro therm made by zoomed (I think) that gives an accurate reading for temp and humidity; it also auto regulates heat by turning on the heat lamp. I mist once a day and my humidity is perfect (80-90 %) heat stays right at 82 (mid level in the tank...allows about 80 at substrate level)

You have to prepare your substrate well to get a head start on humidity. Weather its loose or in the brick I soak my eco earth and wring it out so that water is not 'pouring' out of it, then put it in the tank. 3-4 inches deep.

Ten gallon tanks can be hard to manage without a auto digital regulator like the one I meantioned. You have to have ventilation as well so you can't just seal up the top (you know this) to keep humidity. The uth suck IMO for heating. I use exclusively lights for all my frogs.

Hope this helps.

I spent:
Tank 40 bucks new
Light fixture 15 bucks new
Bulb 8 bucks
Hydrotherm 70 bucks (these cost about 100 at my pets art)

I would reccomend a Zilla digital heat humidity gauge. They are about thirty bucks. They work awesome. If you can't afford the 70-100 bucks for the hydro therm I mentioned at least you can get accurate measurements.