You can get fairly ripped doing home workouts if you execute proper routines which keep the intensity up...the goal being to workout, hard, until you hit 25-30 minutes. You'll need to adjust your routine to be more difficult if you're finishing at 30 min and you're not beat. If you're beat at 15, lighten the workout.

There are probably 100 or more body weight exercises out there and with a $100, you can buy some useful house supplies that double to be used in a kickass workout.

For example. For $40, you can buy 2 five-gallon water cans. A gallon of water weighs just over 8lbs. 5 gallons will get you over 40lbs. Carrying these around your yard, doing lunges, for shoulder shrugs, or used for deep pushups will do awesome things. You can also water your plants like a boss.

A 20 lb sledgehammer is great to swing around and can be used to strike the ground for a killer ab or lat workout. Can also be used to smash stuff.

door frame pullup bars are okay..I like the workout but it's tough to find one that feels comfortable. I'm 6'5" so it's not common that I can find a door that allows me to "hang" like I'd want to.

I'm not familiar with HIIT but some other routnes you can check out are

farlek (speed play), which really helps to break up the monotony or simply running.

if you wanna get to your lactate threshold quickly (ouch), try tabata training. I've taught tabata to help get folks to do more of an exercise in the same amount of time. (say...doing 60 pushups in 1 minute from their start of only doing 40 pushups in 1 minute).

and probably the most important. working out is great, but go have fun. You're getting stronger, getting faster. Go use that to experience things that might have been troublesome in the past. Pick up a new sport or go hiking.