Well first of all what you and your gathering of believers do with our money is up to you. You are the stewards of your money and not I.
Theologically however YES in the OT or old covenant times God instructed that a physical temple be built. There was a reason for it for it was to reflect the idea of what goes on in heaven with the High Priest (Jesus) coming before God. That was the purpose for the earthly temple with the slaying of animals to cover men's sins.
That whole thing however has been swept away now with Christ our High Priest in Heaven, and the curtain of the earthly holy of hollies was torn from top to bottom. God doesn't recognize physical structures on the earth as his temple in current times but rather that we are the temple, that is the people are the temple of God.
"....you also, like living stones, are being built into a spiritual house to be a holy priesthood, offering spiritual sacrifices acceptable to God through Jesus Christ." 1 Pt 2: 5
So men may buy or construct psychical buildings but do we see in the Book of Acts they are instructed to do so? I think what we really see is money going to help the poor, resources to yes support ministers to be in the ministry and much can be said about that where there should be balance. But I don't see even the logic of using money to build big buildings.
I sometimes wonder how many people's lives would have been blessed that instead of building colossal structures costing millions if the money coming in could have helped people more by helping pay poor people's medical bills, heating bills even helping them get educated with a trade. As for where does one preach, well I know someone who did pretty good preaching on hilltops, lake shores, fields and who knows....maybe we can do so today?