If you just say what passport you are on and if you are planning live in Thailand with Thai wife OR just want to visit as a tourist you might get answers. Plus write in better English, because right now you're just asking random muddled questions, but not providing any information on what you want to do.
the money isn't to pay for visa. You pay for the visa when you apply in your country of residence. Cost for that depends on what embassy you apply at. The 400k money is to show immigration when you apply for 12 month extension, because THAT is the rule for a 12 month extension of stay based on being married to a Thai. The extension costs 1,900 tbt.
up to you. You didn't bother to say what passport you had. And so had to guess you were not Thai because you asked about visa because you are married to a thai. If not Thai you need 400,000 for marriage visa. Or can fly in on tourist visa. If Thai you don't need visa. Perhaps give some facts people can use to advise you.
House has nothing to do with visa. Apply for non O based on marriage in home country. Enter Thailand. Open bank account. Deposit 400,000 tbt. Season money. Apply for 12 month extension of stay. Can get a re-entry permit to leave and come back during the 12 months. But need to be back to apply for another extension. But if you are building a house why are you leaving?