You could buy some asic's an have them hosted. But I would tend to think that simply buying bitcoin and holding it would be more profitable and maintain liquidity. ROI would be a long time as well.
Buying bitcoin and hold them for a long time is always effective but mining will generate you more bitcoin and you can hold them until blockhalving to make more profit.
The profit spread of buying vs mining with 90+% of btc already being mined and the work/capitol involved in mining now make purchasing the coin directly the "best" bet.
Time is money, the time & logistics involved in mining vs buying isnt worth the spread in profit differences imo. (edit to say these days , in the past mining was the way to go!!!)