@Zigzag03,

So a few things to help out.

Your entire network will not be slowed by adding slower 'nodes' or extenders, only devices that are connecting through your extender will be affected. However, the lower maximum does affect the performance that will reach your RV. Range and Interference will all subtract from your speeds, so stronger high-bandwidth connections are more likely to provide your RV a strong enough signal for daily use. 

Depending on the range needed, you may struggle no matter what to reach your RV. How far away is it from your home/walls?

If it is nearby, you should be able to get away with a Range Extender, but you would likely prefer the streamlined connections that come with using an Access Point, or wired RE inside the home.

At a consumer level, the only outdoor extender that we have is a part of the Deco Mesh System, which you could consider depending on the age and state of the rest of your network. The Decos area available for Outdoor Use and offers PoE(Power-Over-Ethernet), allowing you to actually place the extender closer to the RV. For just your RV, you could use the Deco in AP mode so you wouldn't need to reconfigure your whole network. If you are able to wire the node, you could look at one of our Omada Outdoor APs, but they do require a wired connection.