Should I get an arm lift and Brazilian butt lift at the same time? I want to recover for both at the same time.

You can possibly have them both done at the same time but you would have to be evaluated in person to be sure. It might be reasonable to stage them for the reasons you  mentioned.

Should I get an arm lift and Brazilian butt lift at the same time? I want to recover for both at the same time.
I read that it I its not good to have an arm lift and BBL at the same time because you need your arms when you are trying to recover from a BBL. However, I would like to recover from both at the same time because I only have 4 weeks of vacation. If I get them separate I would need more time to recover from both at different times. Has anyone performed both of these on patients that came out fine during the recovery process? I also would like to have my mono lipoed too.Great question!
The Medical board in the state of Florida has a very defined requirements to maintain a physician license.  For an elective in office procedure, the board restricts liposuction to one liter of supernatant fat removed form your body if you combine liposuction with a arm lift. 
I recommend you have an in person consultation with a board-certified plastic surgeon that you feel comfortable with.  Please seek a plastic surgeon certified by the American Medical Association or the American Osteopathic Association. Review their online results, patient testimonials, patient performance reviews, seek a surgeon who has done tens of thousands of BBL procedures and who specializes in the aesthetic surgery 100% of time.
I wish you well through your surgical journey toward your goals,
 James S.McAdoo DO FACOS, 
 AOA board-certified plastic/reconstructive surgeon, AOA board certified general surgeon, micro surgery fellowship, BBL specialist