Just in case you want this information, I was able to bring my cellular signal from -100 dBm to -50dBm at home using these three free devices from the carrier:
I used my Android phone to check exactly which of the three devices worked best to give me the best cellular signal strength:
At the same time, I set up five different access points within the house to get the best coverage for WiFi (in case I wanted to use WiFi calling):
The three devices are two different types, where this one is a pure cellular signal booster (the other ties to your router):
To see exactly when each of the three micro towers was the one I was connecting to, I set up this IMEI catcher which pinged me visually and with a beep whenever it saw a new cell tower not in the whitelist:
In the end, I was able to figure out which device of these two types gave the best signal strength overall for my needs inside my house (and in my yard).
Feel free to ask questions if you want to do the same for your home because I boosted both my WiFi signal strength (using transmitters that dwarf the power of a typical home WiFi router) and my cellular signal strength without any investment in money.