Pfft. I have an open top tank. They look nice :P But I understand if you are concerned about your betta jumping. Luckily my female betta is not at all prone to jumping. Or you could keep it and have it like 2/3 full that way there is NO way your fish can jump out. If you will only have one fish you wont even need a filter. You can add some bog plants above the water line and make a cool riparium to fill up the space above the water line.
Ripariums look amazing...
PS: My financial aid check is what is left over AFTER tuition has been paid. I spend most of it on gas & textbooks though :( 40 min commute everyday...