Good point, around here everyone I know who grows outside gets bud rot to varying degrees in the fall.
Not a problem you only learn from asking questions.
For 4 plants to get ready for outside, you could get away with a 2x2 ft tent. I would go 4x4 ft because once you start to grow you will want to grow 24/7 365. Always get more than you need, it’s future proofing your grow lol. For lights get a cheap Chinese led 600w they are more like a 400w in reality for a 2x2 or a 1000w for a 4x4 90$ eBay. They are good for vegging never used mine for flowering.