Wireless router <$40

So here's what going on. Why house is made of very dense and thick concrete that blocks most signal that's coming through. My computer is upstairs and I have my router downstairs. I was able to barely get any signal from where it was located, like about 20% at most, and my mom just moved it a couple of meters and now I can't get any! I've tried to convince here to move the router to upstairs since it would still enable both of us to utilize the router, but she's not willing to have a cable running through the stairs. Ethernet cable would not work because of the said reason and because there's no way to drill a hole through the wall or ruin the door. 

 

Long story short, I need a new router that would give me the ability to get actual usable signal that is under $40, or at least a better adapter for the price. Right now I have a D-Link DWA-525 as the adapter and a ZTE F660 as the router

Have you tried ethernet over power? Something like this: 

http://www.newegg.com/Product/Product.aspx?Item=N82E16833181158

Do you have carpet? If so just run ethernet and tuck the wire under the baseboards.

Sadly, those things are not available here. Even if it is, I can't find it anywhere

Nope, everything's under my feet are just tiles and concrete

How about any ventilation ducts? It's a pain to lead them through, but it works

My house was designed to be without ventilation ducts since everything is meant to be cooled by AC, so that is crossed out as well :/

What do you mean by those Ethernet over Powerline devices not being available 'here'?  Just buy them online.

The bandwidth capabilities on it are SHIT but eats only 30$ and the length is amazing. Dont watch netflix and surf the web at the same time though. http://www.amazon.com/XWR100-Dual-Band-Wireless-Internet-Router/dp/B003S4ZJW4/ref=sr_1_1?s=electronics&ie=UTF8&qid=1375903058&sr=1-1&keywords=vizio+router

On sale down from $80

http://www.newegg.com/Product/Product.aspx?Item=N82E16833122472 

I like netgear products and $40 for 802.11N is a good deal.

 

My parents don't trust online purchases for having lived in Nigeria for a while. They still don't trust it even if they've moved back.. So online would not be a very great idea