I learnt how some farmers do it with combined agriculture, increasing area productivity and lowering financial stress until the main crop starts to give you some income.
First they plant Papaya. Red-lady , Vavuniya type or similar hybrid variety.
As the plants grow they plant banana in vacant places and treat them well. Then you can slowly introduce coconut to the approved span .
Papaya start give you income within 1 year and continue for 2 - 2 1/2 years.
Banana also give you some income until coconut start producing enough in 3-4 years time.
I introduced pepper also to the system . You have to plant gliricidaa (ඇල්බීසියා) 6 month before planting pepper.
These days, in Matale, Kurunegala Districts agri people are removing old varieties and give new hybrids for better production. They give some financial subsidies to buy planting material. I think 80,000 per Ha.
Try to plant a row or two of arricunut trees in boundaries for extra income.
For papaya you need non-water logging or well drained land and lot of water supply during dry season.
If you provide irrigation to coconut in dry seasons your harvest will be increased considerably.
Cinnamon is also very good and easy to grow but you have to find peelers and fulfill their various demands. Peeling needs lot of manpower and hard working trained people.
In Ambalangoda and nearby areas they do it for 1/3 of the income. In other areas you have to share 1/2 of the income with them , I heard. That is after spending for fertilizers , weeding, security etc. from your pocket.