Electronic Alarms and Home Security Devices - Need suggestion on Home security camera

I have a 3500 sq ft house. I do have the basic alarm security system installed, but since I travel all the time, I would like to see the house with my eye remotely while I am away. I heard (I also read some, not much) there are internet connected security cameras can be installed to serve this purpose, here is what I like to have:
(1)4 cameras, 2 inside, 2 outside, prefer wireless because it is not easy to run the wires inside or outside of the house. (2)Able to watch the video any time on the internet. (3)Both Motion activate and/or schedule the video on time. (4) either use a computer or standalone box(DVR?). With these requirements, can some one help me with: what type of device/hardware (brand) that I shoud get ? and how to set it up, and also, roughly how much the system will cost me ? Thanks.

If you want to do this with any real degree of quality and reliability, it will _not_ be cheap.

The best and simplest solution is to use a DVR, most of which have remote viewing software. Typically such units have inputs for 4, 8, 16 or more cameras. They record to a hard drive, and generally have ports for connection to a wired network (ethernet).

Hardwire where you can. Wireless cameras cost significantly more than wired ones, and are less reliable. Each wireless camera needs a receiver that connects to the DVR. Remember, each camera _still_ needs power (which can be from a nearby outlet)

You _can_ go with IP cameras, which can be individually viewed, but they cost a _lot_ more.

Camera system setup is a bit of a "black art", but it's not too tough.

If you just need minimals, you might be able to make do with a strategically placed webcam.

Thank you for the information. I did read a little about the DVR and the camera itself, but still not very clear on how can I access this DVR which is in my home, from a remote location/computer. Do I need some sort of network capability to do this ? what kind of network set up do I need ? Also, What is IP camera ? and What is webcam ?
( I saw a webcam on the top of my laptop screen, but never know what it is ?)

I read some more on IP camera and webcam. I am starting understand these items now. looks like webcam is a cheap way to do this... but I will read some more before I sink the money into it....