Lodging, transport, food, and expenses for travelers in Iberia.

Lodging.

In Spain and Portugal there are Hotels, and Hostels (Hostal, Pension, Pensio, and similar). Hostels tend to be cheaper, and basic. But not necessarily so.

Youth hostels of IYHF are usually the cheapest, cleanest, and most friendly. If friendly you can ever truly call the two nations.

Exceptions:

a Hostel in Granada is further from the center, and a little more expensive. Season price: € 17.5, while private hostels some take 17, some 15. Mind, that Granada is inland, so Season prices should be a bit lower than on the coast. But that is not everywhere true. Not in Granada.
Normally, price is between 12-15 €, if a hostel is non-demanding (maybe decrepit), or not located in a popular place.
In fashionable places they may charge 17, or even 20. Some - 25 €. Even in fashionable places, off-season, prices of Hostels are slashed greatly. On September 15 everybody drops the price abruptly. For example, from 17 to 14.
However, there are no rules. It is a wild west. Hostel owners tend to be unruly. For example, in Madrid one has ripped me off for 17 € off season, for a tiny cell with only a bed in it. When in high demand they never bargain. - Take it, or leave it. Especially that they see you in the middle of the night. You may be lucky to get a decent, even a spacious room cheap... Or equally unlucky to get a tiny expensive "match-box".

Another exception: a youth hostel in Barcelona, named Hedy Holiday Hostal (at c/Buenaventura Munoz). It is cramped. Too many beds per square centimeter. No space to keep your luggage. You tend to smell the neighbour. When you order a bed there, there's no guarantee that nobody sleeps in it while you are away. You come back at night, and still have to bother with locating another bed, and demanding some new clean bed sheets. In the morning the owner of the hostel puts on an artificial air of concern, and tries to appease you. But you know the situation would not change.
I do not understand how they got a licence from IYHF. Perhaps nobody bothers to complain.

Look for an accommodation booth, or office. It may be at railway, and bus stations. "Turismo" (Tourism Information Center) helps too.
They exist in many places.

I don't remember how they are called in Spanish. You find them easily. These are handy in getting the complete choice of lodging and prices in one place for the whole town. They call on your behalf every possible accommodation, according to your budget, and preference of location. In no time you have the room. Just be there at the "accommodation booth" no later than they close in the afternoon. Or else, you are stuck. I don't remember, perhaps they finish work at about 16:00-19:00 hours. It is best to inquire the working hours, and phone number of the "Turismo" or "accommodation booth" of your next destination in advance. Ask for it at your current location before leaving.

In Barcelona - Hostel Kabul - is cheap, centrally located, and has lots of beds. When you call, they tell you to come over - it has places available. When you actually come, they are usually full and don't care what they told you before. They don't accept reservations by phone. They "serve" only on arrival.

In Barcelona hostels tend to be full any time of year.

If you are prepared to pay more than 17-20 € per night, then you may find the search a bit easier. But there's no guarantee either. There are always plenty of people, who pay more than you.

Public transport (busses, trains, airplanes).

Busses in the north of Spain hate bicycles. They tend to refuse taking them aboard, or charge big fees.

Busses in the south of Spain readily take bikes. A driver waves at the bottom of the bus, as a matter of course. At the bottom there is always a large luggage compartment. They charge no extra fee for a bike.

Suburban, or seater trains throughout Spain have special space for bikes - just a bare floor with no facilities. Sometimes there's no special space. But you can take the bike anyway. Always free of charge. Conditions may change. Ask in advance.
Sleeper trains do not have any facility, and are not used to bikes at all. You must arrive early, and negotiate. There's a great chance they reject you.

Public transport in Portugal hates bicycles. Trains on the south coast even officially prohibit taking them. Although, all busses and most Portuguese trains do have special luggage rooms.
A bus driver, or a railway train tender needs to be coaxed a long time. Then he may agree to take a bike. You may try asking at a ticket office. But all ticket offices in Portugal will tell you that bikes are not allowed. You need to negotiate directly with a driver.
Only a few trains around Lisboa allow bikes for a limited distance. Perhaps they think that cycling the remaining distance is healthy for you.

Try spending as many nights as possible on the open air. This saves costs. I spent roughly half the nights outdoors. It is not very reasonable to pay for a room, when all you do is just sleep there, and go outside for the rest of the day. Small towns are suitable for outdoors. Because you don't have to travel far. So, you can visit them in the morning. However, some small towns do not have any open wild space near by. Example is Cadiz. - On the western coast of Spain. It is all concrete. It is located on an urbanized peninsula. Nearest green space to sleep is over the bay, perhaps 15km away.
In big towns sometimes it is possible to stay in parks on the outskirts. Hide yourself well, though, from stray thieves, murderers, or hooligans. It is better sometimes to stay in a hostel at least so that you may wash, and sleep better occasionally. Spend your money only where you have to. And then use the occasion efficiently.

Take hostels as little as possible. Yet do not strain yourself. A hostel may sometimes be to your benefit. Sometimes you might stay in one hostel... Leave the luggage there, and tour the environs without your sleeping bag. Sleep in another hostel... Then return, and continue your journey. May be a bit more expensive. But convenient. Remember you are on vacation. It is not a job. You don't always have to carry the full weight around.

Food.

You would expect about 5, 10, sometimes 15 € per lunch. Portugal is slightly cheaper than Spain. But only slightly.

In general you would first look for eateries, which offer an unlimited meal for a single fee. You pay once, and eat till you quench the hunger. That's what a traveler, especially a cyclist needs. "Taking away" is most of the time prohibited. But sometimes the staff may agree to let you fill your traveller's pot, because they throw away food anyway.
In Spain the "single fee" eateries are usually called "Buffet libre".
Madrid has one. It is located by the side of a square, a few blocks west of Gran Via, at its northern end, if I remember well.
Barcelona has it too. Name: "Lactuca". Address: ronda Sant Pere 17. Just north east of one of the central "Placa de Catalunya".

Cheap eateries may not offer a choice of local or traditional food. But local food nowadays is more of a myth, a commodity. Also sometimes you would not want to eat local food.

Once, very hungry, in Granada I ate a lunch for about 18-25 €. It consisted almost solely of a chunk of meat. Not cooked thoroughly, hard even to chew. Later I learnt that undercooked meat, sometimes with blood still not drained, is a "specialty".

Next day I found a cheap eatery on a quiet street, still not far from the center of Granada. It is called: "Tiscar". Address: San Juan de Dios; 3 blocks away from avda. de la Constitucion. It is a restaurant/cafeteria. It has a "menu" (choice of 3 courses) at 5€. The term "menu" might be one more "synonym" for "Buffet libre". The menu at this eatery is not plentiful. But you may complement it with an additional dish to end up with 8€.
Fish skin is not scaled. Avoid fish, unless you want your mouth full with chewable scales. I don't know if this is traditional in Spain.
If I remember well, this eatery is in a sport where a few Hostales and Pensiones are concentrated.

Expenses.

You should expect to spend about 50 € per day on food, lodging, and transportation. Do not panic, if you spend sometimes more. You will try to spend less at other times... The 50 € is an average.
Take hostels as less as possible. But do not strain yourself.
Iberia is not very friendly to credit cards. Keep some cash for the day.

Make an arrangement with your relatives at home. If you run out of money, they would put more into your account. If you loose the credit card, they would send you a new one (perhaps with a courier). Do not put a lot of money into a credit card. Only enough for the journey.

Will write more later.
Questions are welcome.
You may write me through the main page.
You find my further comments on transport and food here:
http://andrius.saugokmedi.lt/dviratis/gabenimas
It is in Lithuanian language.
Here is another page on safety:
http://andrew.saugokmedi.lt/bicycle/security
It is in English. It explains hazards of travel in Lithuania. But it also gives an idea how to pick a spot for an outdoors stay overnight.

Below is my draft of account of travel through Pyrenees in Lithuanian language.