android phones? a little help on plans?

so my lil sis and i are looking to upgrade our phones as soon as possible. we have our upgrade available right now. problem is my parents don't want to pay for an upgrade so we are looking at the pre owned certified upgrades. the thing with that is all the free upgrades are smart phones or flip phones with no key board. with is a problem due to the fact that my sister sends 8,000 texts a month. i send and recive about 1500. so since a flip phone with know key board and almost no extras on it won't work with our constant need for texting. is there any way to get a android phone with out a data plan? or can we get an android and cancle out the internet (like put a lock on it). thats how our current phones are (locked internet). but if we did have a data plan and didn't use the internet would we be charged for it...like the number of mins we are on the internet. but since we won't use it would we get charged. and further more would we be able to use apps on our android or would that use the internet? so if we wern't alloud to use the internet could we still use the apps?