At the moment I only have the 2 lenses, the 14-42 and the 45-150, both kit lenses I believe. I am looking to get a cheaper macro lens like the 7Artisans 60mm, but I am just using close up filters for now. I will be shooting mostly things I can find in my local park, ie small bugs, flowers etc, or things I can find in the house when the weather is bad lol. I wanted to try focus bracketing/stacking, but not available on this camera body, so may get a focusing rail to try and do manual bracketing, I have a site to do stacking as I do not have the software like lightroom yet. For now this is all trial and error for me as I am still working out what I like and don't like. I seem to favour close up to landscapes, that may be down to being new to all this, or maybe it is just that flowers, bugs etc are just easier to photograph.
I doubt if a body with focus stacking is any where near what your budget was
The 45-150 is very good for close ups, light and easy to use, and you can get back a bit from the subject, useful when it will fly away, combine that with a X1 or X2 screw on close up lens, and you will get some good results. Do not fill the frame with the subject, the screw on lenses will give good results, but any possible loss of image quality will be first noticed at the edges of the frame. Most times when a shot doesn't quite look right, it is not the lens errors that can be seen !
For bracketing, you can try:-
Set the camera to manual focus, and focus on the centre of the subject, then at the far part and close part of the subject, at the same time make a mental note of the focus indicator on the camera screen. The, starting just outside of either the far or near position, take a series of photos changing the focus slightly each time until you get just outside the other end.
It gets quite easy and quick with a bit of practice, and works quite well.
I use Affinity for stacking and merging, both for focus and HDR. The G5 can take a 5X1 exposure bracket, and the setting can be stored in C1 (or which ever you choose) for instant access.
Using the 45-140 lens, you could probably get away with using a flash, possibly with a couple of reflectors (can just be styrofoam or some card with crumpled kitchen foil stuck to it) near the subject.
Just about any flash will work on the G5 used in manual mode, but be sure to use a modern flash designed for digital cameras, as many old flashes made for film cameras may fry your G5.
I have a couple of Nissin Di466s that integrate fully with all the Panasonics I have, and if I need more I use separate flashes with light triggers.
I also have some LED light rings that fit on the front of the lens, they work quite well for small things usually indoors, haven't tried the outside enough to say they work well
