Resin kit has quite a big difference in handling from injection plastic kit.
One important note: Gunpla is made by Bandai in such a way that it's actually half toy half model kit. Hence even without much work n paint, the kit looks pretty good. On other hand, resin (though now there r some that comes in different color) usually comes in one color. So for those who havent painted fully a kit before, resin is big no no; unless u like your gundam looks yellow color.
Even if your have some experience in painting gunpla kit, with no knowledge on "basic modeling skill", resin is also not recommended.

So what's "basic modeling skill"? a bit hard to explain... mebbe we look at what a resin builder has in his arsenal of tools, u will have a clearer picture what kind of skill level needed.

A resin builder most likely will have:

- drill bits n pin vise, brass rod of various sizes (for connecting pieces together. u need to drill holes on both parts, cut a brass rod n use that to fix n connect, eg the leg to the groin part)

- panel line scribber, chisel (at least some experience in panel line scribing, coz most likely u need to rescribe or make panel lines equal depth n width. Also for wide panel lines, usually need a chisel to flatten the base of the panel line)

- sand paper, sanding block, file set, putty, polyster putter (at least quite confidence in covering seamlines n filling up holes. if u think filling up seamline gap and covering sink hole is troublesome in gunpla, u ll not like the hundreds of tiny "sand hole" - direct translation on resin's surface, which are result of air trapped in the resin.)

- file set, knives, lots of putty (should have experience in tackling mold lines, fitting issue in gunpla. resin suaully have more mold lines n the fitting is not even 50% as good as gunpla. Hence a lot of sanding n minor modification needed. one of the basic task is, if on one piece of part, there r 2 different height surface, u at least should have confidence in making them the same level)

Other stuff that looks like they r not related to modeling:

- thinner, container for water, soap, brush (at least should have some experience in washing n making sure the surface is clean n free of oil in gunpla. If one thinks gunpla surface is 90% clean n oil free, try this: pour some engine onto the gunpla piece, wait for 2 weeks until the oil is dry on the surface; now, let's try clean it off until primer can sit tightly onto the plastic. This is the first thing in Resin building: cleaning)

- hair dryer, heater n other heat generator (resin tends to warp, like 1000% worse than plastic. So is pretty everyday work that u need various ways to heat up and make the warpped part straight again)
I hope i m not too potong stim. btw if u know tkting or mgs2u.com, u can contact him as ask for some guidance. i think he's working on resin now n will continue to focus on that for trying to promote resin building among the young generation.

Hope this help