All undertaker MUST by law do a 'basic funeral' this is a simple but dignified service. They do not like people knowing this and will go out of their way to get out of offering it. Do not buy flowers from the undertakers they put at least 100% markup on them. The basic funeral has just 1 hearse for the body , you will have to supply your own 'bearers' to carry the coffin.
We have 3 undertakers in my hometown and at least 5 more a few miles away a close friend had to arrange a funeral for her Dad recently. She phoned them all and kept going back with the quotes and asking them to beat it, like for car insurance !, she eventually got a deal for £1200 when the first quote was £3500 for the same thing. They don't like you doing it but it certainly gets the cost down most people do not argue and just accept whatever they are told by the first one they contact.
If the person who organises the funeral is a pensioner or is on benefits then they are eligible for a 'funeral grant' from the government this is repaid out of the estate if there is enough cash in it, all funeral directors are compelled by law to offer a 'Basic funeral' for the amount of the funeral grant , but as I said they HATE you knowing this and will even deny it exists.