Social anxiety, unable to confront friends who take advantage?!

So I have this friend, and he comes over to my house every single day, uninvited. Now, I enjoy hanging out sometimes, but this is over kill, and he eats at our house( I live with a friend) all the time as well. I cant afford this. If I'm cooking myself dinner, its unavoidable that Im expected to cook for everyone, and when I don't offer all the time its like they think Im being rude. He's also made a habit of eating food off of my plate! Ive even told him not to, and what he think hes doing, but he doesnt get it! I need time alone. I do not like being around people every single day, (my room mate and I have different schedules which works out well.) So, how do I get some personal space from this guy? Ive dropped hints, he doesn't get it. My room mates gone most of the time he's here so she doesn't care. I feel like I'm getting walked on. I've resorted to locking the door and pretending I'm not home on occasion, because if I don't answer he'll call me to see where I am( I dont pick up), or resort to coming over 2-3 times to knock on the door in one day, until I answer the door. I don't know how to handle this. Its very clear that we are nothing more than friends, so I dont think thats an issue here.

Setting of boundaries is in order here. Let him know that you do enjoy hanging out with him but you need alone time. From here out, he can only come over [insert situations in which you would like to have him over] and enforce your policy. Call him out every time he oversteps the line. If he takes offense, that's his problem. Dropping hints won't help this and you shouldn't have to hide in your own home. I didn't do this enough with friends before and my priorities got all messed up. Never again.

if the hints didn't work..it's time to be blunt.
1. "you can't be showing up unannounced 2 to 3 times a day..i really do need some time to myself, not trying to be rude but this is too much".
2. " i cannot afford for you to come over here and eat everyday..i'm sorry, i can't"
3. " i really don't like it when you eat off my plate, i'm not your gf i'm your friend"

i get the impression he wants to be more than friends..even though you say it's very clear. if he just wanted to only be platonic friends its' doubtful he would show up 2 to 3 times a day or eat off your plate..something's up here.

at any rate he is not respecting your boundaries and you will need to enforce them, there is no other way.