It depends on age and condition of property !
$600-$700 for a 2BR 800 sq ft condo in good condition PER YEAR is a good ball park for R&M .. PLUS capital upgrades which is called a "reserve fund" in most strata/condo boards, say $50-$70/month.
or for a 1500 sq ft + 800 sq ft basement single family house:
Using a 20 year average:
one new roof every 20 years: $20,000
2 hot water tanks: $1400
3 carpets or hardwood floors: $9000
4 paint jobs: $6000
landscaping: $2000
new bathrooms: $6000
new kitchen: $5000
plus plus plus ...
.. say $40,000 to $50,000 in 20 to 25 years .. easy .. or $2000 to $2500/year for a house .. or about $200/month on average!! Some years 0 .. and then, boom: $9000 plus 3 months vacancy !
Now, assuming house is in decent condition, and the roof is fine for 10+ years, as is the kitchen or the bathrooms .. that'll leave paint, carpets, fences, landscaping, grass, doorhandles, hot water tank .. an "average" is hard to guess as you may have 2 years with 0 R&M and then you may have to re-carpet the whole house, paint it, fix 2 showers and 2 toilets and fix the hot water tank for $8000 all in ..
Budget your "cash-flow" accordingly i.e. keep a healthy reserve !!! Best would be an appropriately sized line-of-credit that costs you nothing until used !!
Some people have drowned in rivers one foot deep on average !