Wooo Mama! Do you have your hands full or what!
If it were me, I would use all the manipulative tools in my toolbox!
They obviously like coming over. They wanna be there. There one tool to your advantage. Your son wants friends. Another tool. You supply ALL the food in that house, as well as access to games, TV etc... Tool!
I'd be calm, cool and relaxed (if you flip out or try to get all "Mommy" on them, they may wind up just making fun of you and leaving - which will break your sons heart and also ruin any respect they may have ever had for you.)..... But - I would just simply make clear house rules
Not emotionally charged.
Not intimidating.
Not complicated.
A+B= C
Wanna grab a snack? Ask.
Wanna play a video game? Help clean up first.
Wanna watch a movie? Don't throw popcorn at each other.
You may have to go so far as putting a lock on the pantry. No joke. You may also have to stow away some of those favorite video games until they realize you are in control.
They need to see that you're on their side! You are the one that dishes out the good stuff - but you're also the one that can dish out the bad. THEY'RE the ones that decide which it'll be.
But remember! Dont get aggressive. You'll open yourself up to mockery - these are adolescent boys. Be nonchalant. Have the "I don't really care" attitude, without the "not caring" part.
Save your temper tantrums and "HOW DARE YOU!" speeches for internal dialogue that will motivate you - but don't start throwing that at them.
You're holding all the cards. Just play 'em right! You can do it!
....also - if all else fails and it really is out of control... peer pressure is great. Let your son know that this is absolutely not going to happen. Period. So if he wants his friends to come over, he better help you keep them in check. Don't let him turn into one of those kids either!
And talk to parents. Explain what kind of problems you're having, and that you'd love to have their kid over, but that its getting to be impossible to deal with them.
That may help.
All else fails - your home becomes off limits, but hopefully you'll find a better solution!
Best of luck!