Thank you everybody for your suggestions.
Some of your ideas, though I think are perfect, simply would not work in my apartment with two desks being in high traffic area and another desk being a very small bedroom. So although I do think to do a floating floor with vinyl or laminate, it simply would not work with the layout and change in flooring, sharp corners of the laminate sticking out over the carpet, etc. I would've loved to have hard surface and not really adjusting well to the whole carpet thing.
Also, where I am, I don't have Walmart or Sam's club, have Costco but no membership, and though I do have BJ's membership for couple more months, the closest BJ's is an hour.
I also didn't find anything on craigslist in my area.
What I ended up doing is expanding the search area on craigslist. I planed an outing in the state park yesterday which is about an hour away. Since I was going to be driving that way anyway, I looked on craigslist for areas along the drive. This was on Friday. I found someone selling brand new floor mats for carpeted floors and they had multiple mats available. But were selling them at the garage sale on Saturday.
I got in touch with them, explained that I will be in their area on Sunday and would like to pick up the mats then if they would hold three of them for me. All was arranged and yesterday I picked up mats, 3 for $50, brand new, and only 10 minutes out of my way on the way to the outing.
I have to say, I am very pleased with my purchase. And I definitely see a huge difference in using the new mat vs the one I had which was for hard floor. The new mat is much thicker and stand up to carpet much better and I don't feel like it will crack any second.