A couple of notes:
You can breed shrimp well in a smaller tank (7.5 gal to 10 gal range) and it might be good to try this with a small tank to get started with.
A smaller tank (like a Fluval Ebi or a standard 10 gallon tank) is going to be cheaper to buy pH buffering soil for (in the US Aqua Soil seems to be the best option if you need to lower the pH) since you need less volume. A smaller tank also gives you the affordable option of using RO water without having to buy an RO unit up front. You can probably get two 5 gallon water jugs and have them filled once a month at a local fish store for ~$5.
I would recommend getting either a Fluval Ebi or a 10 gallon tank and using pH lowering soil (Aqua Soil or the Fluval Shrimp Stratum soil that comes with the Ebi and is sold seperately as well if you can't get Aqua Soil) and picking up a few jugs of RO water at an LFS. Buy some neos from someone on this site or Aquabid (Red Cherry Shrimp, yellows, blue pearls, snow white, red rilis, etc.) and start with those. Neos don't require the pH lowering soil or RO water but once you have success with them you will already have the tank set up to allow you to keep more sensitive species and then you can just move your neos to another tank and move the new shrimp right in.