Originally Posted by zAr
4) Wait and hope a boat comes along with a diesel just the way I want it....
Everybody has their preferences (I'm very happy with our propane stove/oven and bulkhead heater), but regardless I would not make the existence of an installed diesel heater and stove the litmus test for which boat to buy.
Find a boat that best fits your needs and budget, then modify it over time as you see fit. Price, length, displacement, draft, sailing performance, sail and gear inventories, etc would be much higher priorities as I tried to eliminate prospective candidates.