I am currently building a house here in Mexico, different regarding the laws, and the price, as we are doing the whole thing for about 20-25k!
What we have decided to do is to move in as soon as it's liveable and then the finer details (painting, tiling etc) we can do whilst we are living there. This is going to save us money on the rent that we are paying and we both enjoy DIY and are quite handy with it, so we can do that in evenings and weekends.
The process is very enjoyable in terms of being able to design your own home but the build can be stressful.
My plot is on the same area as the in-laws and it's right in the downtown of the city. The floor area we have is 10x10 meters so not too big but the area next to us of the same size is owned by my wife's uncle and we are going to buy it from him and I will put a small English school downstairs and extend the house on top.
We were very lucky that here in Mexico, when you work you build up housing credit to buy properties, and with her mum having 20 years of this credit and never having used it, we got 20,000 pounds of credit, which will cover the build and we have some extra cash that we can fund if we need it.