Guys that only want one thing.. ?

Okay I'm 19 years old..I had so many past relationships where guys would use me for my money and try to convince me for sex.. People always tell me I'm too nice and end up playing me..and taking advantage of me.. And I hate it! So ive been taking time from relationships it's been a 1/2 year so far but now that im focusing on myself I have 3 guys or soo i use to talk to and know in high school saying " let's chill" and down inside I know they don't want to hang out and catch a movie.. They just want sex.. And I'm not falling for it this time..for instant this guy text me yesterday saying that I never text him and all this bs and �He made me feel like a bad person.. So I was like we can hang out.. And he was like we can kiss and more;) and I was like no kissing and more and he was like smh after I known you for so long and I didn't text back after that.. Ugh what can I do to get rid of these guys that just want one thing (sex)..??? �what can do to find out in the future when I'm ready for a relationship in guy just to make sure he is not one thing guy?