I have seen the Rino liner cost is over $100 per running foot, so a 30' like mine would be well over $3,000, more than I wanted to pay.
I installed Herculiner on my roof, basically a brush on bedliner material. Cost was right around $1,000 with all the cleanup supplies, mask, and the 5 gallons of material at $125 each gallon. Only adds about 25 pounds to my roof.
It does smell for a long time. About a week to get the chemical odors out of the RV. IT is nice that there is no more white streaks going down the sides of the RV.
Another manufacture makes a 2 part coating made just for RV's. Easy to apply, less toxic than Rino Liner or Herculiner, and has a longer "Pot" life once the catalystist is put in, if the product is kept below 55F.
Fred.