I'd strongly consider
https://www.1up-usa.com/product-category/bike-racks/
Check out some you tube videos on 1upusa....our rack (two fatbikes, under 25# @) tilts down away while still attached and cable locked (for theft purposes)....don't know if a 3 bike rack tilting down would allow enough clearance to the ground AND allow opening the rear half due to the last bike handlebars striking the ground (AND depending on the combined weight of the 3 bikes plus ~ 75#s of rack...it may be too heavy if attempting the hefting solo while squatting or kneeling).
They now make a heavy and super duty rack to accommodate heavier downhill mtbs or even an E bike.
Dave