In which Nairobi suburb are there budget guest houses frequented by mainly non-tourists?

I am a Western tourist and I need to stay in Nairobi for one week. I'm looking for budget accommodation near-ish the center (max 12km radius from the Ethiopian Embassy).

The room must be safe, i.e., I must be able to lock the room, go in to Nairobi without worrying (too much) about the staff stealing in my absence. I'm not too concerned by the suburb itself; even a densely-populated commercial or residential area with corresponding risk of crime is fine. I want to avoid places frequented by (mainly) tourists (e.g., Karen Camp, Manyatta and Milimani backpackers).

Budget = max USD 10 pppn (KES1000)

In which Nairobi suburb are there plenty budget accommodations where one can easily find a room? I'm looking for a suburb in Nairobi with accommodation such as I found in Tanzania.

I'm currently travelling in Tanzania. In cities (e.g., Arusha, Dodoma, Iringa) and towns/villages (e.g., Kondoa, Mpemba, Zamahero, Madukani), I stayed in simple rooms (some with/without own bathroom) in guest houses (not hotels, not lodges). The price per room/per night/per person is between USD2 (TZS5000) and USD4 (TSZ10000). The rooms are clean and safe. The staff is friendly and honest. The guest houses are generally not near tourist attractions and have no tourist facilities (e.g., swimming pool,free Wi-Fi, western-sit-toilet). Some lack tap-water and only provide bucket showers. The guests are mainly Africans who are in these places on business.

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