Dwell is a verb, so you need to write dwelling place. Usually we would omit the word "place" and say simply "... your comfortable dwelling."

If you wanted to use a form of the word dwell, you could also say it as "This flat is going to be a comfortable place of dwelling." Depending on what country or region you're in, this phrase may or may not be customary. For example, in the States, we wouldn't word this phrase like this, but in the UK or other parts of Europe, this would be more customary. Either way, you would still get your point across to any English speaker. :)

Hi. The ''dwell'' as a noun couldnt be correct. Instead you can say ''this flat is going to be your comfortable dwelling.'' dwelling place wouldnt be correct either. hope it helps :)