Need Help With Basement Gym Setup/Leveling

Hi there all!

I have this basement space that I would like to use a portion of (or whole thing) for working out.

https://imgur.com/a/SqXYLJd

Problem: the basement is unfinished as you can see, floor is uneven so I want to know the simplest and most cost effective way to make it usable. I will be putting in a short squat rack towards the right corner and a deadlift platform in the middle. Bare minimum is the area circled in red for the rack + platform at least, but I also have other stuff like elliptical, punching bag etc. so if can do whole space that'd be good but not absolutely necessary.

Dimensions: less than 156sq.ft (exact = 12ft 11in x 11ft 7in, ~6.2-6.3ft height)

Caveat: I'm a renter. Landlords are super chill about whatever I want to do down here, but since not mine I'm not looking to shell out several hundred/thousand to make this super nice, just want a flat area to put my equipment (at least my platform + rack).

Things considered:

1. Concrete Grinder - seems easy enough but I'm sure I'm missing something. Looks like I can get from Home Depot for like $200 bucks for few hours, prep area (assume just clean it?), then put on mask and make it smooth. Just not 100% sure if equipment rental includes something for dust collection or if that's something to be concerned about. Also not sure if I can simply grind highest bumps to match the lowest or if there are any more serious things like housing codes or etc to consider. Would love more info.

2. Self-leveling - also looks straightforward, but perhaps more tedious? (patching areas, prepping with glue, marking with tiny marker flags, etc.) and with ceiling height being low already I imagine this may make it lower since it'll raise floor in some areas. Also not sure if this is indeed a simple DIY as it looks, I've seen various videos on different methods some much easier than others. Would love some insight here.

I am a pretty resourceful, quick learner and solid DIYer but this is a new area that I think Reddit strangers could be super useful for. Also to be honest, I'm not opposed to letting someone else do it (kinda prefer it for less headache if within reason $$$).

Would love thoughts on the two methods above or if there are others I'm not thinking of. Really want to make this happen since I'll be here at least 2 years and I'm a pretty religious powerlifter having had a whole setup at my last place in a guest room, with this house having the basement I'd prefer to use this dingy area and spruce it up and actually have a guest room for use lol. Don't really want to spend money and hassle of going to a gym ever again..

P.S. I am located near Boston.

Thank you!!