real estate question? What do you think?

real estate question? What do you think?
I have enough to buy an older mobile home with about an acre of land outright(40,000), and to put about 3,000 into it- I would have the furnace and a/c cleaned and serviced, replace water heater, patch and repair walls and paint, rip out all carpet and put the .25 stick on tile everywhere and then area rugs, in the summer and winter(san antonio) if needed I would put plastic on windows. I dont think that would come to over 3,000(already have rugs)then live there for 2 years-expect 100 more on utils than I pay now, no pmi, half the taxes so that evens out and the 1,750 I had to put toward my mortgage a month I can put in a high yield savings account, then in two years I could build a house with 42,000 down, own the land and all utilities already be there(this place is out past lackland afb a ways in the country) then I would be able to afford the house I want without maxing my budget and it would give the market time to get a bit healthier is this a bad idea? Am I paying too much/lil
if I bought a home I wanted it paid off in 5 years- would have to get an older home and would spend 15,000 of my down payment on a geothermal heat pump and radiant heat cool flooring so... would take me longer