Unless you are trying to pay off the loan, which is doable, you should not have to pay more than 2 installments of the loan. Only the 1st one if the RNG is kind. However, until you get comfortable with the game, you may need to min-max your initial characters. If you want to go with dungeon delving optimize them for combat, both by class and race. Maximize the MC's charm, it makes a big difference early on. Give them both the sex trait of Life Power so they can heal with sex. Recruit Daisy early, she has the Prodigy trait so she picks up classes pretty fast. Harvest the materials in the dungeon, its much faster than the towns. Take the thief class on one your initial character so you don't miss dungeon loot. Do as many dungeons as you can. Get started on the Mayoral election. The early part of the game is the only part that takes some focus and planning.
Actually, You don't need to know any of that to clear the first 1000; those are just one of the 'better' ways to do it, not the ONLY one, not even close. Any party with 3, sometimes even 2, characters without negative combat traits can clear an instance of goblin cave, though you should run from battles with 5+ enemies (or 4+ if your party isn't strong enough). Search the shop and pick up 1-2 cheap weapons, or just choose Fighter Guild to get a free sword. The shop might not have those weapons on the first day, but you won't have enough Loyalty points for the slaves to learn to fight anyway, so just check the shop on the next day (reload if needed). You don't even need to clear it in one go; just proceed enough to get 2-3 slaves to sell, and come back if your party is exhausted. In extreme case, you don't NEED to fight ANY battle at all; you can run from all of them except the boss fight at the very end. The clear reward can easily give you 100+ gold per run.
Basically: 1. get two slaves that can fight
2. get 1-2 affordable weapons (clubs or knives)
3. proceed through a goblin cave (if you can't clear it, you should aim to get at least 200-300 golds worth of slaves to sell before exhausting yourself.)
3.5. get one more weapon (opional)
4. rest for some days, learn some skills and buy another instance of goblin cave to clear
5. repeat 2-3 times, and you'll have enough money to invest into other things
6. learn the game and do the rest yourself