Having owned many non rv trailers in commercial service and doing most of my own R&R/maintenance on their suspensions I kept 3' long cut up RR ties for cribbing under the frame in 4 places. I turned them at angles to eliminate them rolling over. I also used the front landing jacks to stabilize and take most of the weight up front.
I raised the frame till the tires cleared.
Depending on what type of suspension work was to be done I left the tires on or removed them. They can be handy to roll a axle out and back under the trailer.
With the axle hanging I then used a couple of hyd floor jacks under the axle for releasing pressure on the equalizer bar and shackle pins/bolts.
Several ways of doing trailer suspension work....much depends on what tools one has and experience of doing this type of work.
I never worked under a trailer that sat on just jack stands ....thats just me. Others may be comfortable with doing it.