Some weight stations leave the scales on even when the station is closed. if this is the case No charge..
HOWEVER at best you can only do axle weights by driving SLOWLY over the scale and noting the first weight (When front axle mounts the scale (Total (Gboth axles) and last Rear only.
YOu really neeed to know the "Wheel weights" and on most Weith stations you can not do that
To do that you neeed a rlat5 scale. or segmented is nice. park so the full axle is on one setment (Each axle a difrerent setment.
Get total axle and vehicle weights
Re-park so only one side is on the scale (Get weight on that side)
Do the math for the other side.
YES. usually that type or scale costs.
Optional www.rvsafety.com (I think its comn) has a link to a serfice that ror a reasonable ree will call you and interfiew (What tires do you hafe. have that info handy) and come out and do all the work safe for driving the RV for you.