Your 2 big expenses are obviously going to be the pop top and bumpers, then add in a rear tire carrier and deluxe box. If you read through this forum, you may be familiar with the options out there.
You can fab up some bumpers or have that done, otherwise thereís a handful of options, most of us go with Aluminess. There are some used Sportsmobile pop tops that come up for sale once in a while, I think thatís the only way to get into one of theirs, as I donít believe they install them on customers rigs anymore. So then the choice becomes gtrv or Colorado Campervans, get in line! Camburg makes lift kits for 2WD vans, or depending on where youíre located, which is? thereís a host of shops that might be able to help you out-Ujoint, Agile, Boulder offroad.....Youíll want to address your electrical layout if you start adding stuff-separater/isolator, adding a dedicated deep cycle (agm) battery to your rig if it doesnít have one already and maybe look at wiring in a larger inverter that runs off of it and then thereís a converter for shore power plug in, water systems, the list goes on and on......
Welcome and good luck! Lots of info here and some amazing build threads
'03 Ford E350 7.3L Diesel
(de)SMB'd Custom RB-50
Quigley 4X4 w/Deavers & Agile Offroad's R.I.P. package
CCV High Profile Pop Top