You need to start as early as level 1, if you plan on going the extreme mini base route. Medals also greatly impact matchmaking, and the higher the base score, the more sensitive your base will be to medal count changes. Mini bases limit structures, turrets, and traps that are not essential. At least not essential from a PvP perspective. Wars will depend on the squad makeup and preferences. The mini base will depend on squad center troops, guard reserve, buffed walls, armory edges, and the matchmaking advantage to cover for the lack of turrets and traps.
Turrets and Traps are at the heart of the mini base decisions, which start as early as level 1, and by level 3 you will already be hitting the top end threshold for turrets and traps. Structure/Turret ranges for mini bases:
Turrets ............ 0-4
Traps .............. 0-4
At every HQ level, you gain the option of adding 2 more turrets. In an extreme mini base, you don't add any turrets and forgo turrets at even level 1. More practical mini bases will add 2 turrets at level 1 and max out turrets at level 2 with 4 total turrets. Mini bases don't usually add more than 2-4 traps at most. Most will wait till they hit level 8 to add 2 traps, then possibly 2 LAAT traps at level 9. I have seen 6 total turrets work, but the base becomes very sensitive to medal count gains and you will see higher level bases at level 8 and above. Recommend you wait until your medal count and skills level off at level 8, before making the decision to add a possible 5th and 6th turret, if you decide to go the mini base route.
Just from a perspective standpoint, base scores will go from 100 at level 1 to 3300 points at Prestige (rounded). Of that total, turrets make up 1,650 or 52%+ of the total base score. Traps add 492 or 15.7% of the total. That's why mini bases limit turrets and traps. Taken to the extreme, if you did not add any turrets and traps, your base score would be 991 at Prestige (assuming no Deka's). A maxed out level 5 has a base score north of 990, so you can see how big turrets and traps are in the mini base decision. From a practical standpoint, I rarely see more than a level or two difference in matchmaking, even with mini bases. I have not pushed medal count down to the min though, so that could be a reflection of medal count. There's also the practical limits, where you need resources to upgrade units, and you can't get that attacking a level 4 opponent if you are at level 8 or higher. Any more than a one or two level matchmaking differential would be self defeating.
Some people will hold off building credit markets, alloy refineries, and Contraband Trade Ports, since it's better to loot other bases for resources. My general feeling is that at 66 points max for the credit market and alloy refinery, and 27 for the trade ports, it's probably a wash at best. They are additional walls in effect and the base score impact is minimal.
Squad Level: 50
We are always looking for active players. We have a squad of 25+ members, and we war twice a week. We have maxed out our Perks. We like helping new players, so all players are welcome!