Here are a few sources of info. This is a very promising industry in Bangladesh as per capita consumption of milk, cheese and yogurt is on the upswing, being several notches below per capita that of India and Pakistan.
a. You need to buy/rent land and get necessary permissions (bribe etc.)
b. You need to hire and budget to pay competent staff
c. You need to buy the local or foreign bovine dairy stock. Imported cows from Australia or other countries produce far more milk.
d. You need to build the milking shed and automated or semi-automated milking equipment as well as sanitation infra
e. Ensure quality feedstock and insemination stock can be sourced or is available from suppliers or can be grown within the premises.
f. Be ready to start small with maybe a couple dozen heads of cattle, then keep room for expansions.
Here are a few links.
A study was conducted to analyze the dairy farming sector of Bangladesh from an economic viewpoint. Primary data was collected from smallholder dairy farms using survey questionnaires. A Cobb-Douglas production function and multiple regression models were estimated to analyze farm milk...
pubmed.ncbi.nlm.nih.gov
It may appear alien to many that traditional milk collectors and sellers, known as Goalas, used to visit households with their milk containers every morning to sell fresh milk. And households used to buy from them.
www.thedailystar.net
Eon Group has established the country’s first automated dairy farm in a village of Badarganj upazila in Rangpur.
www.thedailystar.net
Indian info source - not applicable completely to Bangladesh reality
A step-by-step guide to starting dairy farming in Bangladesh, business plan, dairy breeds in Bangladesh, and objectives of dairy farming in Bangladesh.
www.agrifarming.in