Lot's of decent advice here. Tracks over tires. Get a bigger trailer. I've got a 2015 E35 with all the bells and whistles... love the thing... I have a 1' bucket, 2' bucket, 39" grading bucket, and an auger with two bits. I do feel like it's the smallest really useful machine though (at 7500lbs) available. 329s, 330s, 26Ds, and the like (~6000 lb machines) are really too small for much of anything besides landscaping and moving loose materials. They just aren't heavy enough. If I bought one again, it would be an E42 which is a little heavier, has a little more reach, and would still fit on my 16k trailer.
I agree with you that renting is tough, unless you have a block of time you can set aside and focus to make the daily burn worth it. A good helper who knows how to run a level and a shovel could also drastically reduce your machine time, rather than going 100% solo.