As far as what materials you can use to replace the floor with is really up to you. There is no "best material" to use. You can use linoleum, carpet, tile, cork, wood flooring, etc. What matters most is what works best for your RVing Lifestyle and that the flooring is put down properly. Some flooring may be easier for a do-it-your-selfer to install.
Please take a look at the answers I gave to the questions below to get some ideas on what you can do with your trailers floor.
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