Mac ... depending on the size of the building/ walls that you're making ... Search for Camo Junkie's "Gun for Hire" and my 1/35 Navy SEAL. We both scratched small wall sections using the same basic technique, just using different materials.
Also search around in the dios forum, etc, and read through some of the threads. A lot of those have buildings/ walls made for the builds.
*edit*
As far as to scratch or not-to-scratch ... Weeeelllllllll .... Yes, some people scratch everything while others scratch out of neccessity ... But, there are also those that scratch b/c we prefer to. True while you might be adding more "projects" into your build, all it takes is simple planning. Get a good idea as to what you want to do and take it one step at a time. IMO, I scratch b/c I learn more about the subject when I build on my own, that, and buying one AM kit after another gets the wife hot ... and not the kind I like.
The best piece of advice I can give you is this ... why not start out scratching!?! Instead of playing around w/ a $20 resin piece, why not experiment w/ a $3 piece of styrene or styrofoam? I've gotten great results from great AM resin pieces ... but I've also been asked where did I buy that wall section from when it was just a 30-min scratch-build from a block of styro. It's up to you though ... Bottom line ... either way, just take your time and do your homework prior to starting.
A good plan is always perfect until you cross the LD ... but cross w/o a plan and you'll be immediately shot in the face.
HTHs.