Slow WiFi in 1 corner of the house
I live in an 1100 square foot, 2 story condo. I have an Archer A7 Wireless Router. it is located on the 2nd floor in the North Western corner of the house. It works great all over the house, even on the patio, except for the downstairs South Eastern corner, extreme opposite of the router location. I have both a laptop and a TV with a Google Chromecast in that area. I can connect but we get drop out. Watching Netflix for example, we get constant buffering. This area is about 35 feet from the router location, accounting for the difference in elevation. The condo is wood frame and drywall construction.
I can have the Cable Modem location moved, so that I can put the router in a more central location but the cable company will charge about $100 for that. It seems like it would be better to put that money towards a mesh system, however, it seems like this router should work in a place this small.
Does anyone have any advice to get better performance out of it? Thank you for your help.