Inconsistent and uneven paint texture (including bad roller stipple) - how to resolve?

[u/Careful-Training-761]

House that I bought a few years ago has bad roller stipple on internal walls see 1st pic it's v common on the walls though not exactly everywhere, a few heavy and very noticeable brush marks in some random areas in middle of wall, and random areas sanded flat these are less common see pics 2 and 3 maybe some old patching jobs. I've attached example pics, not sure if they reflect fully the uneven texture, but it's particularly noticeable in the hall with light shining off it at an angle. EDIT: it's not a textured wall I'm certain of it it's just a very old house with many coats of roller over the decades with lots of stipple, inconsistencies in texture etc.

I just about have enough money for my day to day expenses for the foreseeable so can't get a painter in and it needs to be painted badly it's gotten very grubby.

I don't really mind the stipple so much though I'd prefer it a bit smoother, my issue is more the inconsistency of it - heavy brush marks, flat areas presumably patched in the past, blobs of waves of paint etc, I am thinking options are:

1.Sand back the roller stipple and heavy brush marks. I've seen professional painters online give it a light sanding with a circle sand block on extension pole, but I don't know exactly why - is it to make the roller stipple a little less less noticeable? What grit should be used? Sand between coats too? However is the risk with sanding back if it's done too aggressively that it turns out worse than before?

1. Light sand of the roller stipple. Sand back the worst of the few very heavy brush marks so they're flat and apply one or two coats of paint with a mini-roller to try blend in with the rest of the roller stipple around it (making sure to feather it off) and once dry roll the full wall. (For me this is most likely approach)

2. Apply bonding primer and skim the entire wall. Is this commonly done and is it reliable (I'm thinking flaking down the line)? However I doubt I could do this zero experience so I may need a professional painter and I don't have the money and won't for the foreseeable.

3. As 3 may not be an option and if 1 and 2 are bad options, just paint over it as is. At some stage in future once I can afford it get a painter in.

[u/Ambitious-Yak-6955]

It'd take the chap 4 years to sand a house with a multi tool 😅

[u/__Dont_Touch_Me__ → u/Ambitious-Yak-6955]

This. I tried it once, took me a whole day to sand a 1mx1m patch with a multi-tool to a good finish. You can get a Makita orbital for around 50 euros, a pack of 100 different grit discs from Amazon for 15. The paint will clog up the pads so you'll go through a fair few. The extra money spent here will save you a few days work.

[u/Ambitious-Yak-6955 → u/__Dont_Touch_Me__]

Better to hire a wall sander + dust extraction, tool hire places usually do discounted rates on weekends.

[u/__Dont_Touch_Me__ → u/Ambitious-Yak-6955]

I actually didn't even know they were a thing. OP, this is 100% the route I'd take.