Hi,
A Jacuzzi is going to be FUN! Why not?
ALL you have to figure out is the water that you need to bring along, how to heat it, and what to do with it when you are done. With a Cyclone Toyhauler, you will have a 10' X 8' space to install it, and they can come with a PAIR of 100 gallon fresh water tanks. They come with a 6 gallon hot water heater, and you could buy a Eco10 water heater for about $150 and that has a 57,000 Btu burner, and will instantly heat about 10 liters per minute by 90F, so heating the water going into the tub is solved!
So do you want a single person or two person hot tub, or Jacuzzi? You would need to install it yourself though.
Or look at this place. They will build the trailer any way you like it.
http://www.horizonsrv.com/The Cyclone that I was looking at recently has twin bathrooms! And a patio that folds out of the side just behind the entrance door, along with the rear ramp becoming a second patio! There is a bathroom near the garage, and one on the upper section of the bedroom. The reason I like the other bathroom is my daughter's wheelchair does not climb stairs well, and at 100# she is difficult to lift nowdays. . .
http://www.heartlandrvs.com/index.php?p=35&c=toyhaulers&sc=CYC&i=CY+4200+All+New+Concept%21&view=floorplans&fcmd=showfplanSo it is possible to do just about anything in a RV.
Fred.