I've tried many different boards to get a solid connection through walls, floors, etc. This is the best I've found. Use them as outdoor sensors and sneak into the garage through three walls.
π‘ Izokee ESP-01 Serial WiFi Transceiver Module with USB Converter, Compatible with Arduino
8 Review
10GBase-T SFP+ Transceivers, 10G Copper RJ-45 SFP+ CAT.6a, up to 30 meters, π Cisco SFP-10G-T-S Compatible, Ubiquiti UniFi UF-RJ45-10G Supported, Fortinet, Netgear, D-Link, Supermicro (Pack of 2)
9 Review
π Ximimark 1Pcs ESP8266 Network Relay WIFI Module 220V 10A DC 7-30V 4 Layers Board TVS Input Automatic Protection: Enhanced Home Automation Solution
8 Review
π‘ CM19A R.F. PC Transceiver for X10 Devices
8 Review
π uni USB C Hub with Ethernet Adapter, 4K HDMI, Gigabit Ethernet, and 3 USB 3.0 Ports for MacBook Pro, iPad Pro, XPS
11 Review
π USR-TCP232-410s: RS232/RS485 Serial to Ethernet Adapter/IP Device Server with DHCP/DNS Support
4 Review
HB-UMLS Sabrent USB 2.0 Hub with 4 Ports and LED Power Switches for Each Port
12 Review
π StarTech.com NETRS232 Serial to IP Ethernet Device Server - DIN Rail Mountable - Serial Device Server - Serial Over IP Device Server (Black)
4 Review