Correct, you can use FHA 203 K refinance loans for renovations on a home you already own, but there are loan limits. These limits are based on counties, see https://entp.hud.gov/idapp/html/hicostlook.cfm
to check your county. You can use a conventional loan such as FANNIE MAE HOMESTYLE for renovations. These have a higher loan amount than FHA, most counties are $453,100. At this time you cannot use a Jumbo loan for renovations.