I don't liveaboard
but I think it is doable but tight for that size of boat and budget
Things you would need to consider would be your boat slip, hydro, insurance
and all the nickle and dime fees
that a marina charges (ie. pumpouts). Then you would have living expenses which can be as frugal or extravegant as you desire. Then there are repairs
and maintance which is variable depending on the age and condition of the boat and your level of skill and need to fix things. The problem with cheap
boats is that they are cheap beause they need a lot of work.
In the Toronto area my guess marina related fees
would be about $6-8000 per year or more for that size of boat to live downtown and maybe less out in the boonies. You would need to find out what your local marinas
charge, however. Some marines here also require surveys to ensure the boat is seaworthy
enough to grace their docks (a $400 fee).