Mic-Distance Long Affair

Yoohoo ladies and gentlemen, I have a question here.
How far away do you stand/sit between the mic? And how low do you set your microphone sensitivity to?

I usually stand up and have my mic on the table(I don't have a mic stand) while I record because I'm afraid of making my vocals peak. The table is like up until my hips so it's like, a few feet away from me mouth. 
However, recently, I started recording closer to the mic by putting a chair on another table and placing the mic on the chair. It became clearer but I wasn't belting completely so I can't tell whether it would peak when there's full belting.

How far do you stand away from the mic when it gets peaky? There's natural echo in my house so I'm wondering if that also affects the recording too much. I leave my windows open and put a bunch of pillows and towels around the mic when I record but the echo is still slightly there.

Peaking is just a sensitivity issue. I tend to stand relatively close to the mic (to where my pop filter is) and change my settings as I go. 

The best way I can describe this is when I'm doing vocal recording for acting jobs. Lines that are regular volume I keep around 75% sensitivity whereas shouting lines I'll put around 25%. It's all about just finding the range. If you're doing a loud song, do a few test shouts in to the mic and adjust the sensitivity as you go. Maybe even sing the loudest part as a warm up whilst using it as a level test. It's all about just finding the comfortable range for your mic.

Also, keeping your mic below you does cause problems. Your voice rises up but usually mics only register a certain range so anything outside of that is inaudible or very distant sounding. Keeping your mic low usually just results in your mic picking up a very echoey vocal which no one likes and is far too difficult to clear up most of the time. Another tip I've seen many VA friends do is put a blanket over them as they record. This keeps the sound locked in so only the mic can grab it but it does get very sweaty rather quickly and can be annoying if the blanket keeps slipping. It's worth a shot, though, if you don't use a huge one and are standing.