New apartments and homes may have a video doorbell to allow you to screen callers, but my house is a two-level Victorian that lacks such modern adornments.
My first thought was video doorbells from eBay. You can acquire both the wired and wireless varieties, some with displays fixed to the wall and others with multiple tablets that can be moved around the home. Since my house is two levels, at least two display stations or tablets would be required, which was beginning to move the price north of AU$500 dollars, and cabling the wired systems might require an electrician, as well.

To set up the camera, I plugged it into a PC, installed the software from a mini-CD, and set up the password for my Wi-Fi network. I then navigated to 192.168.1.129 in Internet Explorer, approved the use of the OCX, and the camera view with controls appeared. Two-way audio and video worked immediately both on the set-up PC and other PCs on my home Wi-Fi network, and I could also move the motorised camera. There does not seem to be motorised focus on this model, so making sure the focus and depth of field is correct using the manual focusing ring is a good idea before installing the camera on a wall.
While the camera was working fine, every time I disconnected from the PC, it apparently disappeared from the network. This stumped me for quite a while, until some internet searches turned up the fact that the wireless IP was actually the next IP in sequence, namely 192.168.1.130. Plugging that into the browser gave me access to the camera.
The camera's highest res is 640x480 at 30fps, and you may move the camera remotely through a wide arc, change brightness and contrast, record video or stills, and turn on infrared and audio. The camera also has options to allow for motion detection, automatic recording, alarms, door unlock, and the ability to send snapshots to an email address.

I'm setting up some old, superfluous XP laptops to provide an always-on view upstairs and downstairs, and I've installed the OCX on various PCs in the house, so a camera window is always available.
While the audio works well, it's generally low quality and the camera speaker is low volume. It's fine for relatively quiet areas, but it may be inaudible in noisy areas.
The software will handle up to nine cameras if you need a video surveillance system, but I was happy with the modest investment to provide a security camera at the front door.
With the camera in place, I've yet to try it for screening calls at the front door, but it has let me locate our missing cat waiting patiently to be let in.
Full Bio
Tony is the owner and managing director of Microcraft eLearning and is one of the creators of the AUTHOR eLearning Development System.
