Need an amp for Monoprice 108250s

I am considering building a sound system with 4 speakers. I want a decent sound in a somewhat large room, but I prefer to use 4 speakers spread around the room rather than 2 more powerful speakers. Mostly so that I can play music on lower sound level but still hear it in every corner of the room.



I am going to use Monoprice 108250 speakers, mostly because of incredible price (30$ a pair), and decent reviews. They are up to 80 watts of power at 8 ohms.



I have never set up a passive system and need your help with recommending me a cheap amp. Most people recommend Lepai LP-2020A+ but the output is 20W, isn't that too low for 80W speakers?



Do you know of any amps for under 100$ (preferably around 50$) that can power 4x80W system?



I might also add a sub-woofer later, if I see I'm lacking bass (probably active). Do I need to consider this right now while picking an amp?



Thanks in advance.

Need an amp for Monoprice 108250s