Travel is problem, carrying the part is another. If travel no problem but carrying too many thing back home is problem, maybe you can buy just the casing online and get it delivered, or contact the distro for the case you want.
Everything else go SLS buy, like TP, can save you some money, carry back home shouldn't be an issue. Maybe only GPU and PSU just a bit of weight, the others are either small or light. Just a bit bulky
If really lazy to even head down to sls, then buy all online lor, but gotta tell you that if any issue you still need to go down to sls. Or say you want to buy fans or realise certain connector not long enough, also need to head down to sls, so cannot be lazy one haha. Like me, i total went down 5 time in 1 week to get fans, fancontroller, fan extension, swap my lemon h100i etc etc.. until now, I still need more fans as cybermind out of stock. Also I need to grab a new pair of speaker and FC so probably going to head down at least two more times this month.. LOL
Pray you 1 time fix finish no need head down lor, sibei waste time de!!
Better research on tips and tricks too! Especially the Dont's, you dont wanna screw up your 1st rig. It's quite easy as long as you have study enough!