Sounds like you've got time, but no money- that means rebuild is possible, especially if you go cheap where you can, but not so much buying new parts and getting everything professionally done. Won't be free by any means, but possible.
First thing, obviously, is a good hose down. Don't pressure wash the engine, but you know that.
You said it cranks- do you mean it turns over with the starter, or does it have a kicker?
Good. Do a compression test. On a bike that's been sitting this long, it'll probably be horrible, but that's fine- the numbers will come up as it runs. As long as you're getting relatively even compression across the cylinders, you should be OK, at least for now.
Then- clean the carbs, clean the tank, change the oil, get the manual, RTFM, do a 3,000 tune up, and try to fire it up.
If yes- woo! On to the rest of the bike. If no- check your fuel, air, spark. We already know compression's good. Fix that. Fire it up.
Post video of the first start!