Sometimes we just need a slow plan to get us started! You’ll have your tank one day!
Funny that you mention it, because it just might be how to make the best of some recent trouble with my 110 liter (with a crap ton of extra cash too!).
That can be summed up as neon tetra disease together with an unusually high bristlenose pleco bioload (and consequently much less clean tank) that the previous owner did not experience despite virtually identical maintenance, food, and introducers of neon tetra disease.
These may end up as me having to rehome/euthanize the remaining neon tetras and rehome the bristlenose pleco, at which point my non-aquarist housemate-cousin would want me to only use the tank as a quarantine instead of replacing them with disease-free neon tetras and a normal bioload bristlenose (they wanted to draw the line at 1x 473 liter tank and were not that enthusiastic about my other 2 tanks).
But, with that said, there is a key from the past that has convinced my cousin to give copycatting your setup some serious thought.
Before I had my 473 liter tanks and the fish I do now, I used to have fancy guppies. They ended up producing some considerably colorful offspring which sold for what ended up becoming a rather sizable amount of money, and my cousin also got very interested in the breeding at the time.
They were immediately interested in doing some more of this breeding when I got my hands on the pair of 473 liter tanks and the 110 liter tank, but it wasn't an option because the guppies would become food in the 473s and overload the bioload of the 110 with their babies.
This is where the ease of captive breeding of the zebra pleco comes into play - with each pleco bred, I would be able to get >S100, blowing the proportional profits from the guppies right out of the water. My cousin is interested in this rather large sum, to the degree where they are open to having the 110 liter as a zebra pleco breeding tank if the neon tetras and bristlenose pleco from Reddit don't end up working.
So I'm happy to say that if I do get my copycat of your tank one day, it will have come from making the most of a sticky situation. The only thing to do beforehand is slowly get the money as you say, which I am quite familiar with because I am doing just that to prepare for the setting up of my 2nd 473 liter.
Thanks for the encouragement!