Weak WiFi

[John From Detroit]

One thing you need to do is understand routers... Some are single band (Generally 2.4Ghz)
Some dual (Generally 2.4GHzand 5 GHz. Do not confuse 5 GigaHertz with 5G (5th Generation) completely different things) some are Triple band now days. (I know nothing, I say nothing about the 3rd band).
Now in the 2.4 band there are 11 channels all of which overlap at least 3 other channels. 1 is in a ham band where i can pump major wattage. you can try it but you may get booted... however it does not overlap 6. and 6 does not overlap 11 So if you have two routers make sure the 2.4 part is not hanging out on the same channel.. 5GHz band has more channels but again spread 'em out if you have the ability to do that.
Also make sure both bands have unique SSIDs Some say the PSK's should also be different but truth. Not necessary all mine are something I use the dame PSK for both no problem. The SSID's however MUST be differnet.. IF you use a 2nd router it can be in either "Router" or "Access point" mode but again I'd suggest spreading the channels (Away from the primary router) and differnet SSID's for (Just add "2" to the primary SSID IE. Joe and joe 2) also special charaters like ' and possibly - need to be avoided.... Alpha-nmeric are ok. and a period is ok like SNAFU.NET and SNAFU.NET 2 (I suspect you know what SNAFU means. by the way SNAFU.NET is my "Guest" router (Disabled unless I have a guest then I enable it and give you the PSK)
Back when was in the RV that was my primary SSID.. for reasons you can guess.

 

[Isaac-1]

Let me make that a lot simpler you don't need a new router, get a wifi repeater like a TP Link RE550 for about $80, plug it in (possibly in the RV, or partway between where the router is and the RV) set it up and chances are very good that this will allow you to get wifi at the RV.

Here is a short 3 minute video on how to configure it using a smart phone app

 

[Gary RV_Wizard]

Sometimes the "capacity issue" is just the number of IP addresses the router has available to assign. That's near always part of its configuration and can be changed, but somebody needs to log onto the router itself to make those changes. Which means somebody who remembers the ID & password and can find the manual or download a copy.

But Isaac's advice is probably easier and "plug & play".