Thank you all for your responses!
brownbutterfly, I never tried Precinct Comfort, but judging by its rooms and location, and from similar-hotels, I'm pretty sure it would have been a good deal above my price range. Or maybe I'm wrong.
And post.email - N350,000 a year? That is ridiculously cheap, if it's indeed a comfortable place. I've actually driven past that part of Igando countless times for work, but never stopped by, as I'd already procured accommodation at that point. Although I heard that there aren't too many working generators in that estate.
Hi Hans. I'm back in the US as of November 2013, but, long story short, I decided to up my price and stay long-term in the hotel where I was initially lodging at, Ikeja Central Hotel, near the Oba Akran/Adeniyi Jones intersection in Ikeja (message me if you wan't me to connect you to the owner). A large part of the reason was both the insecurity of my post (I wasn't sure whether I'd be leaving in 3 months or a year) and my friendship with the British-Nigerian hotel owner, as well as its proximity to Computer Village, which I had to visit 2-3 times a week for business. By paying in advance, I was able to get a rate of N3k per day, or N90k a month. It's as nice a budget hotel as you'll find in Lagos, especially considering there is 24/7 power and even semi-decent wifi.
The only other secure, moderately comfortable (by Western standards), and furnished place I was able to find for the 6 month period, after much haggling, was small guesthouse/hotel in Ikota, near VGC (between Lekki and Ajah). They ultimately agreed to accept N400k for 6 months (not including the 10% I'd probably have to pay the realtor). The issues were 1) I wouldn't be allowed to use their kitchen very often, 2) though a short walk from the main road/highway, the side road which the hotel was located on wasn't paved and often got muddy, 3) transport from that area to the mainland, and particularly Ikeja, almost always takes quite long time, and 4) general prices of dining out, entertainment, etc. is higher than on the mainland.
In all, short-term, secure accommodation in Lagos for expats (even for ex-Peace Corps, "backpacking-type" expats like myself who are okay with roughing it up to some extent) is very difficult to find at a cheap or even moderate price. If you're unlucky enough to be with a cheap company that doesn't provide housing, like I was, and you're staying for 6-8 months or less, then your best bet is to scour budget/mid-range hotels and negotiate a long-term price with the owner, to be paid in advance. I hate those expat-bubble, military-guarded housing installations, but even I concede that though Lagos isn't as dangerous as many make it out to be, it's still important for an expat to be behind at least one level of security, at the very least a hotel wall that's always manned by a guard.
If you're staying longer, perhaps a year or more, then you can certainly find moderately-priced longer-term apartment rentals, perhaps even at under N45k a month. However, keep in mind that in spite of the Lagos government's efforts, most landlords in Lagos State expect two years rent all up front. And if you go the realtor route, BEWARE OF 419, as Lagosians say - make sure to go with one who has community recommendations and a nice office, as rental fraud is rife!
If I come back to Naija, then I'll definitely push to live somewhere besides Lagos (or even Abuja)! My favorite areas, which are all much cheaper too, are Jos, Owerri, Ibadan, Asaba, Ilorin, Kaduna, and Kano. Try to get posted in one of those cities!