Say if someone were to purchase a monstrance for a home shrine and wanted the consecrated bread to have and pray to; would this be improper? Are we as lay people allowed to do this?
Can. 934 §1. The Most Holy Eucharist:
2/ can be reserved in the chapel of the bishop and, with the permission of the local ordinary, in other churches, oratories, and chapels.
§2. In sacred places where the Most Holy Eucharist is reserved, there must always be someone responsible for it and, insofar as possible, a priest is to celebrate Mass there at least twice a month.
[132.] No one may carry the Most Holy Eucharist to his or her home, or to any other place contrary to the norm of law…
The Eucharist is not allowed to be kept in private homes for adoration. The only place the Eucharist may be reserved is in a tabernacle in a sacred place. The main reason for this is to safeguard the Eucharist from any possible abuse.
Second of all, we should keep in mind that the primary purpose of the reservation of the sacrament is not adoration but is “to unite, through sacramental communion, the faithful unable to participate in the Mass, especially the sick and the aged, with Christ and the offering of his sacrifice” (eucharistiae sacramentum).