50 Cent can smell the $8 million he'll get for selling his Connecticut mansion, but there are still a few hurdles before he can get it.

As we reported ... 50's landed a buyer for the sprawling 21 bedroom, 25 bath home -- and that buyer intends to turn the estate into an assisted living facility. However, according to the docs ... the sale is contingent upon a couple things.

First, the buyer has to get zoning approval to convert the crib into a retirement home ... and also, the bankruptcy judge has to approve the whole deal.

Fiddy's lawyers want to close on April 29, so everyone's got about 2 months to get their ducks in a row -- and get that money for 50 Cent. Or rather, his creditors.