Enclosed premium
The enclosed premium is the difference between enclosed and open prices for the same car, lane, and dates. A percent with no date, no vehicle, and no count of quotes is an ad. Ask for both prices in writing.
Enclosed transport uses a different trailer from open transport, so the price is its own quote. The premium is enclosed minus open, on the same car, the same addresses, and the same dates. It is not a fee you can add in your head to a national open average and call accurate.
When a percent is usable
A percent is usable when the page names the date, the vehicle, the lane, and how many companies were asked. If any of those are missing, ignore the percent. Markets move, and a specialty trailer is scarcer than an open one. One lane in one week is not every lane.
What to do for your car
Ask for both numbers in writing. Then decide whether weather protection is worth the gap you were actually offered. RideShipper does not set the premium. If a tool shows two ranges, read the date on the tool. The carrier's quote replaces the range.