Comms comment about fuel use is bang on.
You need to gauge how much fuel you need before filling and lighting the stove.
If you don't put enough in you might not have enough burn time to cook what you have in the pot.
Refilling a hot stove is not fun.

If you overfill the stove you usually end up wasting fuel.
Either you let it burn off or (if you can extinguish the stove) you spill it trying to put it back in the fuel bottle.

edit.
I have seen the Trangia stove with the basic windscreen advertised for under 20 dollars.
You might want to ask at REI or a similar outfitter near you.
For example the Trangia Westwind is between $13.29 and $24.85 depending on the seller.
(Westwind is the basic trangia stove with a windscreen/potstand that is made up of three flat pieces of sheet metal.)