Coins are not an issue in the higher regions (I have millions of them in new world) but you might often find yourself short of them in the start of the game, hence I'm writing this guide to manage them well if you're just starting out.
Here are a few tips for you:
Don't buy the high coin equipments. While they might look tempting, you will probably face a shortage of coins thereafter. If you want to buy, ensure you have atleast 10k-15k spare coins.
You need coins for event equipments. At level 35 and completing first quest in isis, you will unlock special events. There's equipment in the event which you can buy and which is better than the coin-only products in shop. I have personally been unable to buy an event equipment because I was short on coins so you should make sure you have a few thousand at all times. Cost would be around 5-10k coins per equipment.
Don't send costly caravans. You might want to send caravans for some wood overnight so you can unlock underground faster, but don't, they are quite costly. You'll end up with more extra spaces but unable to buy anything from shop.
Send apple caravans. The apple caravans are something you shouldn't avoid though. Overnight apples and flour/sugar during day can help in producing quite a lot of apple pies or caramel apples, which are one of the best foods to make in egypt. You'll mostly not have enough resources for grilled fish or berry cakes but you can forever cook apple pies if you follow this. Energy is more important so even if it costs 1250 per night (for 5 caravans of apples), it's worth it in my opinion.
Caravan for coins. If you've saved up enough flour or sugar for producing items in kitchen, you can try your luck at the coin caravans, especially funny money but I personally don't think that's worth it. The other 5 minute one could cause losses if your luck is bad, so the 2 hour is better, don't need to repeatedly check and you're more likely to earn a profit.
Do the repeatables. If you are at an absolute shortage of coins, that is don't have enough to buy equipment from events, do the coin repeatables. If not, I would rather suggest continuing with the questlines. You'll need quite some energy to do the coin repeatable, but if you use that energy to progress instead, you'll eventually stop facing shortage of coins.
Save for older events like Christmas 2015. There's a lot of good equipment for coins in Christmas 2015 but you'll need over 250k coins, so you can start saving coins once you have good enough capacity and regeneration.
Play vintage events. Events released before 2017 available in shop could have a significant number of coins so you can play those to get quite some coins while also getting some good equipments from them.