Just checked with the 98mm motor I "loaded" into the sim (a N motor, it comes to be over 52lbs. Something tells me I need to finish reading Modern High Power Rocketry before I launch into anything of that size.
Weight w/o motor was a smidge over 20lbs (of course this is just an OR simulation (with a cardboard rocket)), and with the highest power L motor in OR I could find put it in at 31lbs.
I'll repeat this though... at this time it is just a thought exercise, and I am nowhere near ready to go out and start buying parts for this.