There may be some confusion for the O.P.
A 13' Scamp with a "Bathroom" may or may not have a shower and/or a sink.
The standard bathroom only included a loo, don't assume that it will have a shower. That takes adding not only the waterproof surround, but a water heater, a pressure pump, a gray holding tank and all the associated plumbing that isn't included with a basic bathroom option.
BUT... be careful what you wish for.... While many owners are perfectly happy with the space utilization in a 13' with the bathroom, others , including moi, have sold 13' front bath Scamps simply because we felt that there was no place to be without making up and taking down the bed each and every day.
BTW: What will you be towing with? The front bath models are a lot heavier than they look, especially on tongue weight