not sure if you need another opinion but...
1)you can change anytime if you submit the paperwork without even telling the caregiver. though it's nice since he'll be growing more than he's legally allowed

2)i use a private caregiver and still regularly go to dispensaries. they're usually just way more expensive

3)my caregiver sells me as much as i want whenever i want it because he always has enough. i've seen a couple ads for free bud but i don't believe any of that. if you have a cool caregiver and a serious condition you might get some for free occasionally but i wouldn't base my selection on that cuz it's not likely to happen.

4)dietblonde was basically right on with the vaporizers. it's by far the best thing to use which is why they're all so expensive. i bought a handheld iolite and it's pretty awesome. just needs refilling. the only place to buy one cheap would be craigslist or ebay and i actually looked without success recently on craigslist.

one last thing. be sure the place you're getting your card has a good price. AFTER i got mine i noticed how easy it really is and how varied the prices can be. i've seen some people pay 120 and others 300. when you really want the card it doesn't seem so bad but you can use that extra money to start off on your wonderful new life.