Is it common for fencing companies to drill into your home rather than use a post

Last summer we rebuilt our fence using advice from The Fence Bible. The advice was great, and the directions clear. The author covered both concrete and compact dirt/rock footers for wooden fences. I'd highly recommend it to anyone building a fence for the first time.

Concrete does risk rotting the wood because of water build up, but that can be mitigated with proper drainage. Dirt footers can be problematic if you have very loose dirt in your yard. Dirt requires lots of work with something heavy to compact it; concrete requires mixing and handling concrete.

We set ours in dirt/gravel and realized it was exactly the right choice when our fence was hit by a car 4 months after we built it. The car shattered two 4x4 posts, a gate, and several rails, a 3rd posts was pulled from the ground, and every other post along the run tilted about 5 degrees including a 6x6 corner post; 10 posts had to be reset in all. Our neighbor (whose fence was also hit) had concrete footers, which were pulled from the ground, or shifted several inches but left in the ground. His footers had to be removed and replaced, and all new posts were required. We had to replace the damaged parts (2 posts, a gate and several rails), but we could reset the others. If we'd had concrete I suspect more would have broken, and we would have been unable easily reset any that had tilted (granted fewer might have tilted but that energy had to go somewhere, hence the assumption about more broken posts).

How tall are your posts to start with? A 6 foot above ground post should have at least 2 feet in the ground in your area. I would be setting them in concrete so you have a good solid base and good ballast. A metal post in concrete won't rust as long as you dome the top of the concrete so water runs away from the post.

I'll share a clever trick that works well and is very fast. After digging your hole for the post, set one or two bricks in the bottom of the hole to set your post on. You will of course have to adjust for height and plumb the post. Then simply pour an 80 pound bag of Sacrete premixed concrete mix around the post dry, right from the bag. Now just pour apx 2 gallons of water on top of the mix and leave it alone for 24 hours. You will have a solid concrete base for your posts without having to mix concrete. Mixing concrete is good, even better, but this little trick is fast and easy.