I know that this is an old thread, but I thought I’d add my two cents.
I’ve had a lap harp for a few years, and just purchased a 54″ high Merlin R harp.
If you have a lever harp of this height or smaller, you might want to consider a Saturn Vue as an inexpensive harpmobile. My Merlin fits, in it’s Colorado Case, with room to spare. My 2003 Vue was $15,000, and I believe that you can get them more inexpensively now. They do well in snow, and are just about the most affordable SUV out there! I drive pretty slowly on the highway (65) and I get about 30 mpg. If I had a pedal harp I’d probably go with an Odyessey, Siena or Grand Caravan. I’d also love to consider a Ford Escape (with about the same cargo space as a Vue!) but it’s quite a bit more expensive–I believe that Edmunds is estimating year old models still at $21,000.