OK, with financial restrictions I can see a build such as your's taking time
I'll admit I went waaay over budget on mine and it took some time to recover
So I'll give ya some leeway
Anything left to buy, or is it just build time now ? C'mon c'mon

This is how I spend my work days, being pressured with parts/time restraints
And ya, you've got all night and 2 days
Honestly though, when do you think you're going to get it salty ? You still have to test your flow - mess with pumps, valves etc ...
At least get the RO running so you're ready
Then you'll get to test out that fancy sliding unit