So for something like that, you might look into Tabular Regressors for predicting future prices based on past price data (and whatever other data you want to use), and Tabular Classifiers to classify expenses into categories you select.

You might be particularly interested in training on-device using the Create ML framework for this... given the historical data would be highly personal and continually changing (if I'm understanding the use case). The Tabular Regressor example that Alejandro shows in the Get to know Create ML Components session is almost spot on with the problem you're trying to solve.

If the textual input is more varied and similar to human language then you might use a Text Classifier. If it's more like terms and you want to include additional context such as price (numbers), then the Tabular Regressor is more suitable.