Can't make the money come in quicker, your best way is to increase your energy so you can do more than one quest at a time. This will give you the capital to go and buy more property and not have to worry about the time it takes to increase. Once you've built up a decent property amount you can have a decent income coming in every hour or so. Mine is about 70k now. Then keep doing the highest quests you can and you'll be rolling in it