How much do y'all usually pay a month on a loan? Right now I'm debating whether or not to save up for my aircraft and buy it outright, or save up 25% of the total price and get the rest on loan.
The principal plus the interest.
The amount of required down-payment will depend on the lender, and after that percentage has been reached, then it's your decision as to what you want to do with your cash flow, and what you want to pay in TOTAL for the aircraft...
Just whip out any amortization calculator and/or apply the "Rule of 72" and you'll know the TOTAL price of the aircraft in each scenario. Paying the interest might be annoying to you after you see the final price tag, with interest tacked on.
Or... you might be one of those people who likes to keep a lot of liquid assets around, and cash is just about the most liquid asset one can have. Of course, in any form of inflationary market, cash sitting in an account is actually losing value, so... your call.
Some people like to utilize leverage heavily, with as little down-payment as possible -- but paying lots more than the aircraft is worth in total interest to the bank.
Others just pay cash for the entire aircraft.
All we can offer here is opinions, but you really have to decide for yourself.
Unlike mortgages, there's no government lenders to back-stop the bank holding your note, or "bail them out" if you default, so expect them to ask for plenty of paperwork showing you're good for the loan.
One technique for that scenario, is to save up the full purchase price, but hold on to it in relatively assured investments that aren't likely to drop with the overall market, and to take out a loan just so you get to hold on to your cash, knowing you could send a big check and lose the loan (and the interest) at any time. This also keeps cash in your wallet for unforeseen maintenance... the engine could blow up tomorrow... if you did everything right and luck went your way a little, and the aircraft is flyable after the forced landing, it might be nice to be able to write a check instantly for the engine replacement... for example, as one technique.
And of course, there's tax implications if you're going to use the aircraft in a business... etc. If you're getting into that, find an accountant who knows aviation and have them work up scenarios for you to your best advantage.
At the end of the day, what you're asking for is something we can't answer for you -- how to manage your cash.
In my personal scenario, the note was taken out before I bought a share of the LLC that owns the aircraft. I assumed (via contract to the LLC) 1/3 of the remaining liability of the note, and had to "buy-in" with the same cash that the other two people did to start the note as the down-payment, but my cash is in the LLC's account, and not at the bank.
The down-payment on the note was roughly 1/8th of the note value, or 12.5% down. That decision was done years before I joined up, so I had no say in it.
The LLC Board (all of us, and yes you need to appoint new LLC owners to the Board, or not... have annual meetings, keep records, and all that... or it's not a real LLC if you ever go to court), can now vote what to do with that cash I "injected" -- The LLC can add it to the engine fund, buy upholstery, keep it a separate fund for [insert something here] and add to it, have the LLC blow it on beer money as Marketing funds trying to lure in more people (ha... kidding, just kidding)... whatever.
This year, we've been discussing amortizing more of the maintenance into hourly rates, since we're not all flying the aircraft equally, percentage-wise. I'm cool with that, as are the other co-wallets.
You also get to decide as a single-owner if you feel like "charging yourself" for things like the engine fund, maintenance, etc... on a per-hour basis, or just forking over the cash when something needs done. In your case, it's all coming out of the same bank account, so whatever you need to do to convince yourself to write those maintenance checks, is paramount. If you need to actually move funds from one account to another on a per-hour basis so you won't touch them, do it.
Personally other than my mortgage, I don't like having loans out for things I can't pay off immediately. Not saying I could pay off EVERY loan I have instantly, but at least the largest one. I would have to pull money from non-liquid accounts that would take a bit, but I could write a check for my 1/3 of the aircraft loan in whatever time it took to get that money out of investments, but it'd hurt future plans... it'd be a very painful "re-assessing" of priorities if that had to occur.
And only you (or I) know how stable our jobs are, etc... so there's too many variables involved. If you own large assets that will make enough money to pay for the aircraft... hey, you're golden... there's just lots of ways to look at it and you have to decide if you want a loan or not. If you go "loan-less" make sure you at least have additional cash on hand to replace the engine tomorrow... that's probably the most expensive repair any of us can face. That's the "safest" way anyway.
Consider having co-wallets and an LLC. It makes the whole thing a little more complex, but a lot less expensive. Especially important if you're not going to fly at least 100 hours a year.
Aircraft sitting on the ground develop maintenance problems in the expensive part -- the engine -- faster than the maintenance costs for one that's flying and having "normal" things break.
Lots of other thoughts, but I have to run... no time right now to finish. Big ones...
Shop a while, and find the right aircraft. Find a mechanic you trust on that type, and don't let someone else do the pre-purchase inspection. Don't skip doing a pre-buy. Check insurance rates before your heart is set on one aircraft, you may find you don't have the hours to fly the "airplane of your dreams" according to the insurance companies, and will pay through the nose to cover it. If you have a loan, you'll be required to insure. If you don't... you could self-insure, but that might be foolish for liability... planes crashing into houses cost millions to the lawyers. Let's see... well, there's more.
AOPA has good owner pre-purchase support. Talk to them and read their articles.