Haha start saving up for a 125.
I would check on craigslist for one if you are broke. It's how I've been able to afford my stuff on a college student budget. I was able to buy my 90 for 200 bucks after saving for a few months. Normally it would be like 1500 or so for the stuff brand new at an lfs. Look for people who are moving. I have seen even bigger tanks for cheaper! Remember gross looking acrylic can be buffed too!
If you want to keep the goldfish for a long time I would move em to the 55 asap and then to at least 100 gallons before they get stunted (trust me that will happen in that 10 if it hasn't already). Good on you for not keeping them in a tiny unfiltered and unchanged bowl of doom though!
The 55 should be good for a few months while you save. When you get the big tank you can pick a few 25 cent buddies up for them since they like groups. Just use the 10 as a temporary quarantine since most feeder goldfish get all types of nasty diseases from handling at the store before you buy them. A few hardy plants like anubias species should be good as well. They may eat them though.
Also if you still have the pleco which I'm going to assume is a common they can get nearly 2.5 or even 3 feet long with a proper diet and water quality. So you should really only keep a grown one in something like a 300 or bigger. Maybe trade it in. Also he will poop almost more than the goldfish so your filters will be tested haha.
For the goldies the ac110 hang on back filter is expensive but a very good choice. You can also stick cheap pothos houseplants in there because they absorb nitrates like crazy, there's a whole sticky on that. Get a strong canister filter too. The more mechanical and biological filtration the better with poopers.
Definitely get a basic heater also if you plan on keeping the neons. The goldfish will be fine as long as the temp isn't in the high end of the tropical range over a long time and room temp remains stable in your house. You can move the neons to the other 55 and do a big school with other inexpensive tetras too with a heavily planted low tech/light aquascape as an idea. In my experience with my uncle's tetra tank, neons are delicate though and die easily. Cardinals are a better choice imo.
Hope that helps! Fishkeeping on a tight budget sucks haha. Just keep looking it up and asking questions here. You will be ok. Goldfish and most tetras are easy.