Well, I don't think I can make it any simpler then such;
- Does Reach stack?
For example: "Reach" weapon property, "Full Extension Fighter Utility 2", "Lunging Strike Fighter Attack 1", "Beastblooded Minotaur Path Feature 16th level", "Eternal Defender Feature 24th level", "General's Weapon" equals Reach 6?
Full Extension Fighter Utility 2
Effect: The reach of the next melee weapon attack you make before the end of your turn increases by 1.
Lunging Strike Fighter Attack 1
You lunge at a foe that thought it was beyond your reach. Encounter ✦ Martial, Weapon # Standard Action # Melee weapon + 1 reach # Target: One creature # Attack: Strength – 1 vs. AC # Hit: 2[W] + Strength modifier damage.
Beastblooded Minotaur Path Features 16th level
Savage Apotheosis (16th level): Your speed increases by 2 and your reach increases by 1.
Eternal Defender Feature 24th level
Godlike Stature (24th level): Your size doesn’t change, but your height and weight increase to 25 percent and 100 percent above the normal range for your race, respectively. You can wield weapons as if you were one size larger, and if you are normally Medium or larger, your melee reach increases by 1 square.
General's Weapon
Power (Encounter): Minor Action. ¤ Until the end of your next turn, your melee reach with this weapon increases by 1.