Around the houses is excessive, but a perimeter fence is not a bad thing. I've started making a horseshoe or square building around my perimeter to limit access for raiders, bonus points if you then add an entry corridor with traps and turrets.
Best piece of advice for early on is get Paladin Clooney as your companion asap, he's a portable meatshield and gives you a weapon that is very strong with a few mods.
Before you scrap any weapons you find check their mods, it's always worth taking out the more powerful ones to save until you get a legendary version. You just need to remember to store the mods in a workbench.