Hi wazuans, I'm setting up a small commercial farm starting next week on a quarter acre of land in kikuyu. Initial costs are the workman structure, sheep structure,tank and fencing totaling to around 130k or thereabout. Planning to start with 4 pregnant dorper ewes.
Feeds: to start with, there's nearby grazing land but I'm also planning to plant some maize, lucern and tulips for making silage esp for dry season.
Any words of advice will be highly appreciated.

Dorper do well in drier areas and as Zenge said, need plenty of land. Hio 130k take it to Laikipia, lease 10 acres(simple fence should do) get a maasai to look after them, water-River, Grass-Plenty of it,Deworm every 6 months, give salts every 4 months. Sheep give birth to twins, 8 months an Ewe can mate. Get a high quality Ram, prefarably from Dorpers Breeders association(change every year to avoid inbreeding)
management
visit the area twice a month.

Small ruminants which include sheep & goats generally,have high probabilities of twinning.

Dorpers in Kikuyu could be a problem as the area is cold. They seem to thrive in hotter areas like Kajiado. You may want to try a different kind of sheep like the Merino, which is accustomed to cold areas.
Also, just like humans, sheep do not always give birth to twins. They can however give birth twice a year depending on your breeding program.