Clint Barton is a sneaky, snarky bastard. For the first month that the team lives in the (newly renamed (and repaired (and, you know, remodeled to include suites for the whole team))) Avengers Tower, no one actually see him (They think he's living in the vents, but they aren't sure).
They know he's there: his suite is full of bows (6, to be exact) and a single duffel bag of clothes (or, a duffel bag and a bunch of clothes strewn across the floor). The archery range has a collection of targets that have been shot to pieces (some of these targets may or may not be pictures of Loki (the stupid, thinks-he-can-take-over-the-world (but can't, because AVENGERS!) mind-rapist)). And, every once in a while, there's a suction cup arrow stuck to the forehead of an Avenger (he never attacks Natasha (She'd kill him! With her thighs of death!) but the shocked looks on the rest of their faces when they get hit keeps the trick entertaining (seriously, he's doing them a favor (their spatial awareness needs some serious work))).
Finally, Clint is forced to spend some time outside of the air ducts and in the company of his team.
("Agent Barton, Sir has requested your attendance at dinner this evening"
"Why?"
"He is of the opinion that, if he is being forced to attend, then so is everyone else."
"How is he being forced? He owns the whole freaking tower!"
"Apparently, the 'disappointed face' of Captain Rogers is a potent weapon"
"Yeah, alright, I can't argue there.")
When he dropped out of a vent into the dining room, the look of surprise on Steve's face (and Tony's "Nice of you to drop in, Ceiling Cat") means that he's smirking as he takes a seat next to Natasha (She thinks it's funny to watch him wince when she kicks him under the table. At least, if they're sitting next to each other, she has less leverage).
"Clint," (apparently, the Captain is getting over his surprise) "It's nice to see you again."
"Yeah, you too, Cap"
"So, Legolas, what've you been doing for the past month - I mean, besides shooting things?"
Clint thought for a second before admitting, "Well, I taught DUM-E how to get into the cabinet where you hid the fire extinguisher".
"THAT WAS YOU?! How'd you even get into the lab?"
The smirk was back as Clint replied, "JARVIS and me are buds."
For a moment, Tony looks like he doesn't know how to deal with that, but all he says is, "Of course he is. You have hands, and you fell into his trap."
"What trap?"
"I hid the extinguisher because he kept spraying me when he thought I had been working for too long."
"And JARVIS wanted to make sure that you didn't overwork yourself. Yeah, he told me. Like I said, we're buds."
"Agent Barton has also gifted Dr. Banner with numerous cups of tea-"
"I thought that was Natasha."
"It is. Sometimes."
"-left art books for Captain Rogers-"
"I thought that was Tony."
"I left the tickets to the MOMA."
"-set up the telescope for Mr. Odinson-"
"That which makes the stars appear closer! It has given me much to speak of with my Lady Jane!"
"-and baked 3 batches of Russian Teacakes for Agent Romanov."
"My favorite. Thank you."
"You're welcome."
Okay, so Clint Barton is a sneaky, snarky bastard who lives in the vents, but he's also a good friend who's made Avengers Tower feel like a real home (He's not going to stop shooting things, though).