Rubber income builds houses
Plantation earnings fund a great deal of the construction here, and rubber prices move on an international market rather than a local harvest. That makes the building cycle less predictable than a grain district, and two years of movement rather than one is what smooths the stocking decision.
Houses built over long periods
Individual house construction across eight or ten months produces many small credit accounts rather than a few large ones. Being able to open a party and see the whole build in order is what turns a running total into something both sides agree on.
Finishing trades and mixed units
Plywood by sheet and area, tiles by box convertible to square feet, sanitaryware by model, paint by pack size. A Kottayam shop quotes most of those in one order, and holding the unit on the item is what keeps a mixed invoice quick.