Trucking: hired movers, ryder rental truck, section appendix

Question
we hired a moving company to come and move our belongings from Colorado to California.  This is a aprox 10,000 pound load and they showed up in a ryder rental truck.  They are now trying to charge us double for the estimated cost of the move and stating that the load was 13,800 pounds. Last year we moved the same household items with United Van lines and it was 9100 pounds. what do you suggest we do to validate that this is a reputable company and that they are not ripping us off.  Also they were 5 days late to pick up the stuff and they still have not arrived with our belongings as of today.  This is a current issue going on and I am becoming very frustrated.  
Thanks

Answer
Barbara, the Interstate Household Goods moving industry is regulated by the FMCSA.  Check this link:
http://www.fmcsa.dot.gov/rules-regulations/administration/fmcsr/fmcsrguidedetail...
and
http://www.fmcsa.dot.gov/rules-regulations/administration/fmcsr/fmcsrruletext.as...
If your mover is not registered with the federal DOT he may have broken federal law by moving you in which case you should report him to local law enforcement.  Hopefully you selected a properly licensed carrier.
Best of luck.