France, Italy, Spain: how to make our money go the longest

'Are long-term accommodation really cheaper' - That will depend on what you intend with 'long term'. Sure a one month self catering apartment (many directories of holiday rentals out there) or a room from an advertiser with airbnb or a month in a hotel room might give a discount, but from what I gather from your post it will be one or two weeks somewhere several times, which is certainly not long term. Negotiation could be in order but your guess how you will fair is as good as anyone's.
'We’ll be traveling by train, unless an area is really much easier to travel to by car or plane as suggested on other posts.' - If other posts do not mention bus then there is something amiss with the wisdom of other posts, when your money matters (as long as you feel time wealthy).
'Wouldn’t the cost of transportation add up to costing the same or more?' - Only you can do the maths comparisons!

Neil kind of addressed the question. It is balance. Mostly you have mentioned potentially higher cost options. Generally long term is something over 30 days. Sometimes you can save a bit staying seven days instead of three but it is not great. Obviously the larger cities you ID are more expensive than small towns but then you housing options may be more limited. There is not a flat answer to your complex question. So you need to do you homework by pricing out you various options. Renting a car can jack up your expenses in a hurry. Advance, deep discount train tickets especially in Italy can be very, very cheap BUT they are nonrefundable and lock you into a set schedule.

And bouncing from six or so major cities, three countries, in four or five weeks hardly counts as living in Europe. More like - traveling in Europe. If you truly want the living in experience you rent an apartment for month somewhere, mingle with the local each day at the markets, bicycle the local streets, spend the afternoon at a cafe, participate in local events. In other words, act like you live there and not just visiting relatives. I think you need to refine your thinking substantially and your expectations.

Carmen, Frank's advice about living like a local is sound. But, if you are referring to having a somewhat stable routine by staying in one place for a week or two, you will definitely have a better grasp of the place than someone who is there for a few days. Personally, I prefer to spend a few nights in places that many people would do as a daytrip, because I feel like I have a better sense of the place if I wake up in it, especially true of popular cities with loads of daytripping tour buses.

Some hotels or B&Bs may give a discount or a free night if you stay at least a week, it's worth asking about. This might work in either a small town or a big city. Renting an apartment so that you can shop at the markets and cook some meals may save a few euro as well.

Paris for a week or two with numerous daytrips will be easy enough, but the French railway system is not cheap, in my opinion. I found Italy cheaper than France overall, but especially in transportation costs. Note that if you are sure of your dates, you can buy tickets for most countries' rail systems anywhere from 60 to 120 days in advance for a very reasonable price (Milano to Venice 9euro, for example), but you can't change the ticket in any way.

The biggest expense of your trip will be accomodations. Renting an apartment for a week at a time can give you extra amenities for less than the cost of a hotel. It is a matter of how much you want to spend and choosing by budget rather than luxury. Having a kitchen will allow you to save some money on meals. Many people book with Airbnb, VRBO/ Home Away and other services. Large cities will be more expensive than small ones but staying close to attractions can save money on transportation.

Early booking can save a lot of money on transportation and can give you more choices for accommodations. The down side is changing plans can be expensive and cancellations are costly. Always read and be aware of policies before committing.

As has been pointed out, staying in one place for a month will be a more authentic "living" experience but you will limit the amount of things to do and see. Figuring out a balance is a personal preference.

Carman,

Many good suggestions/comments.

here is what i have learned. Travel isnt cheap (inexpensive) so lets just get that straight. Expensive will be relative to the persons wallet too.

what my estimates/budget usually work out to is that #1 is transportation. That is usually due to the fact that i have to fly for 10 hours to get onto European soil and that 10 hour flight will usually cost me 1k+ USD round trip. Then my vacation starts. #2 is usually lodging. Since i fly solo, my tastes and what i will use may vary with others here and you. Also, my costs will usually be lower since i do fly solo. WHEN you go and WHERE you decide to stay can make a difference too. #3 on the list is usually activities. That will include admission fees to museums, attractions and such. What can also make a difference will be food. Some places it maybe more expensive to "eat out" than to eat at home.

i found that booking my train tickets as soon as possible is usually less expensive than to do the "wait n see" approach. Of course i dont know when it won't make a difference waiting. Since I'm usually looking at the logistics of train travel from A to B it doesnt take that much more effort to look at the price different from buying "tomorrow" or "3 months" from now and that price difference, if any, will usually make me buy ahead.

Lodging can be determined by using some of the hotel/lodging search engines. Booking.com is one of them. I use it to get an idea on whats available in the area and you can select your choice of lodging types and your budget.

good luck and happy trails.

Accommodations in smaller towns are often cheaper than in big cities, although it makes some difference how touristy those small towns are. I don't like the time and money spent backtracking over any significant distance. Perhaps you will decide that a radius of destinations within 1 hour or 1.5 hours from your base is an acceptable range. I have always been happy with the "moving on" plan. You can set an average budget and accomplish it in the long term, with some stops costing more and some less.

If your destinations are all served by train, then I'd use train. If you'd like to visit several small towns in Tuscany and Umbria that are not served by train, then a car is easy enough in that region. The car also helps you get to cheaper accommodations in rural locations. To connect different countries, it can be quite affordable to fly; www.skyscanner.com.

The single best way to lower total travel costs is to cut back on the number of different beds you sleep and stay put for longer on each of them. Works almost every time.

Tastes and preferences differ a lot. If you can live with the idea of visiting less places and exploring each of them thoroughly, you will stretch your money further. You reduce transportation costs, which is somehow obvious, and you also have more time to seek out cheaper alternatives like cooking at your holiday flat with food you bought at the nearest supermarket, instead of dining out.

You will have a hard time travelling by train down the Spanish coast, especially in Murcia and Andaluzia.