Hi Fmcuam, Ajijic is a nice place, I went there in september.
The closest smart center is in Guadalajara, is called Eurostern and is located at the Minerva fountain roundabout, there you can get the new ones, the cost is almost $190,000 (pesos). You can easily find used ones too, on the newspaper or the internet.
There is this member, RVGringo, very friendly and helpful that might can answer the question about maintenance costs.
Welcome to the forum.